It is a polypeptide and highly specific direct thrombin antagonist whereas it shows no effect on antithrombin-III.
Production:
It is synthesized by recombinant DNA technology in yeast cells.
Mechanism of action:
One molecule of lepirudin gets bind to one molecule of thrombin causing stoppage of thrombogenic effect of thrombin.
Administration:
It is administered intravenously.
Pharmacokinetics:
It undergoes hydrolysis in the body. Its half life is 1 hour. Drug and its metabolites are excreted in the urine.
Therapeutic uses:
It is used effectively in the treatment of thrombocytopenia induced by heparin.
It is also used for other thromboembolic disorders and also causes stoppage of further thromboembolic complications.
Adverse effects:
It may cause bleeding. The drug forms complex with antibody in the body and anticoagulant effect may be elevated, than required, by the slower rate of excretion of the drug-antibody complex from the body.
It may also cause certain allergic reactions of the skin and air passages.
Saturday, April 2, 2011
Heparin
Introduction:
Presence in the body:
It is present in the body in the form of histamine-macromolecule complex in the mast cells. (Its functional role in the body is not much clear.)
Extraction of heparin:
It is obtained on commercial scale from
1. Porcine intestine
2. Bovine lung
Properties of heparin:
1. Unfractionated heparin is a mixture of straight chain anionic glycosaminoglycans with wide range of molecular weight.
2. Due to the presence of sulfate group and carboxylic acid groups it is strongly acidic.
Enoxaparin is a low molecular weight (LMWH) heparin. LMWH are prepared by either chemical or enzymatic depolymerization of unfractionated heparin.
Mechanism of action:
It causes a decreased formation of fibrin by changing the activity of plasma protease inhibitor antithrombin III.
Therapeutic Uses:
Heparin is used mostly in postoperative venous thrombosis and various other thrombotic diseases such as pulmonary embolism and myocardial infarction.
It is also used in extracorporeal devices such as dialysis machine to prevent thrombosis.
Note: Heparin and enoxaparin are drugs of choice in venous thromboembolism in pregnancy as they do not cross placenta.
Administration:
Heparin is administered IV or deep subcutaneously. And enoxaparin is administered subcutaneously.
Pharmacokinetics:
Heparin has rapid onset of action and this action is finished rapidly after the stoppage of treatment with heparin.
Anticoagulant effect of heparin takes place within minutes after IV injection and 1-2 hours after subcutaneous injection. Anticoagulant effect of LMWH takes about 4 hours to take place after subcutaneous injection.
When heparin gets bind to plasma proteins the activity is neutralized.
Although heparin remains in the general circulation but when taken up by monocyte or macrophage system, it undergoes depolymerization and desulfation leading to inactive products.
The drug and its metabolites are excreted through urine.
Half life of LMWH is approximately 4 hours which is nearly double than that of larger species. Renal insufficiency may prolong its half life.
Dosage:
It is given prophylactically in the dose of 5000 units subcutaneously, two or three times in a day.
For diseases which have already been developed, initially 5000-10,000 units will be given intravenously followed by continuous infusion of 900 units per hour.
Adverse effects:
Enoxaparin causes less thromboembolic problems than heparin.
Some of the adverse effects common to them are:
1. Hemorrhage
2. Hypersensitivity reactions such as fever, chills, urticaria and anaphylactic shock.
3. Chronic administration can decrease antithrombin III activity leading to thrombosis.
4. Transient alopecia can also occur.
5. Heparin induced thrombocytopenia (platelet count can decrease up to 50%), which is of two types:
Type-I: which is mild and is for 1st 5 days
Type-II: Which is IgG mediated and is very serious and is with in 5-14 days
Antidote:
Protamine sulfate
Presence in the body:
It is present in the body in the form of histamine-macromolecule complex in the mast cells. (Its functional role in the body is not much clear.)
Extraction of heparin:
It is obtained on commercial scale from
1. Porcine intestine
2. Bovine lung
Properties of heparin:
1. Unfractionated heparin is a mixture of straight chain anionic glycosaminoglycans with wide range of molecular weight.
2. Due to the presence of sulfate group and carboxylic acid groups it is strongly acidic.
Enoxaparin is a low molecular weight (LMWH) heparin. LMWH are prepared by either chemical or enzymatic depolymerization of unfractionated heparin.
Mechanism of action:
It causes a decreased formation of fibrin by changing the activity of plasma protease inhibitor antithrombin III.
Where as enoxaparin binds to anti-thrombin and affects more on Factor Xa as compared to thrombin (Factor IIa).
Therapeutic Uses:
Heparin is used mostly in postoperative venous thrombosis and various other thrombotic diseases such as pulmonary embolism and myocardial infarction.
It is also used in extracorporeal devices such as dialysis machine to prevent thrombosis.
Note: Heparin and enoxaparin are drugs of choice in venous thromboembolism in pregnancy as they do not cross placenta.
Administration:
Heparin is administered IV or deep subcutaneously. And enoxaparin is administered subcutaneously.
Pharmacokinetics:
Heparin has rapid onset of action and this action is finished rapidly after the stoppage of treatment with heparin.
Anticoagulant effect of heparin takes place within minutes after IV injection and 1-2 hours after subcutaneous injection. Anticoagulant effect of LMWH takes about 4 hours to take place after subcutaneous injection.
When heparin gets bind to plasma proteins the activity is neutralized.
Although heparin remains in the general circulation but when taken up by monocyte or macrophage system, it undergoes depolymerization and desulfation leading to inactive products.
The drug and its metabolites are excreted through urine.
Half life of LMWH is approximately 4 hours which is nearly double than that of larger species. Renal insufficiency may prolong its half life.
Dosage:
It is given prophylactically in the dose of 5000 units subcutaneously, two or three times in a day.
For diseases which have already been developed, initially 5000-10,000 units will be given intravenously followed by continuous infusion of 900 units per hour.
Adverse effects:
Enoxaparin causes less thromboembolic problems than heparin.
Some of the adverse effects common to them are:
1. Hemorrhage
2. Hypersensitivity reactions such as fever, chills, urticaria and anaphylactic shock.
3. Chronic administration can decrease antithrombin III activity leading to thrombosis.
4. Transient alopecia can also occur.
5. Heparin induced thrombocytopenia (platelet count can decrease up to 50%), which is of two types:
Type-I: which is mild and is for 1st 5 days
Type-II: Which is IgG mediated and is very serious and is with in 5-14 days
Antidote:
Protamine sulfate
Classification of anti-coagulants
These drugs prevent the clotting of the blood.
Oral Anti-coagulants:
Warfarin Na, Phenprocoumon, Dicumarol (Bishydroxycoumarin), Diphenadione, Phenindione, Acenocoumarol, Coumetarol
Thrombin inhibitors:
Heparin, Hirudin, Enoxaparin, Hirugen, Lepirudin, Danaparoid
Fibrinolytic (Thrombolytic) drugs:
Streptokinase (Plasminokinase), Anistreplase, Urokinase, Tissue plasminogen activator, Staphylokinase
Anti-thrombotic drugs:
Aspirin, Dipyridamole, Ticlopidine, Sulfinpyrazone, Clopidogrel, Abciximab, Eptifibatide, Tirofiban
Extra-vascular anti-coagulants:
Fluorides, Citrates, Oxalates
Oral Anti-coagulants:
Warfarin Na, Phenprocoumon, Dicumarol (Bishydroxycoumarin), Diphenadione, Phenindione, Acenocoumarol, Coumetarol
Thrombin inhibitors:
Heparin, Hirudin, Enoxaparin, Hirugen, Lepirudin, Danaparoid
Fibrinolytic (Thrombolytic) drugs:
Streptokinase (Plasminokinase), Anistreplase, Urokinase, Tissue plasminogen activator, Staphylokinase
Anti-thrombotic drugs:
Aspirin, Dipyridamole, Ticlopidine, Sulfinpyrazone, Clopidogrel, Abciximab, Eptifibatide, Tirofiban
Extra-vascular anti-coagulants:
Fluorides, Citrates, Oxalates
Natural anti-coagulants present in the body
These are of the following types:
1. Those that causes inhibition of fibrin (Fibrin Inhibitors)
These are basically inhibitors of protease. They causes the inhibition of coagulation proteins as they move from the site of vessel injury.
2. Those that causes lysis of fibrin (Fibrinolytics)
These are basically tissue plasminogen activators.
1. Those that causes inhibition of fibrin (Fibrin Inhibitors)
These are basically inhibitors of protease. They causes the inhibition of coagulation proteins as they move from the site of vessel injury.
2. Those that causes lysis of fibrin (Fibrinolytics)
These are basically tissue plasminogen activators.
Hemostasis
It refers to the spontaneous arrest of the flow of blood from a vessel which is damaged.
Hemostatic response:
Vasospasm:
Vessels become spasmodic suddenly after the vessel is damaged.
Formation of platelet plug:
After the endothelium is damaged the platelets get stick to collagen as well as to each other resulting in the formation of platelet plug.
Several factors are released by platelets such as ADP, TXA2, and serotonin which results in further aggregation of platelets as well as vasoconstriction.
Next in the process, aggregated plug of platelets make it possible for the platelet factor 3 availability leading to the sequence of coagulation process further to take place.
Fibrin reinforcement of platelet plug:
A series of reactions are activated after the stimulation of coagulation system. Coagulation system works through two interrelated processes – Intrinsic and extrinsic processes.
Extrinsic pathway:
Extrinsic denotes something that comes from outside. Extrinsic pathway denotes a series of reactions which is activated by tissue factor that comes from outside of blood.
It activates Factor VII by a tissue factor i.e. thromboplastin
Intrinsic Pathway:
Intrinsic denotes something which is found in body part. In the intrinsic pathway proteins for the activation of the process of blood coagulation are present in the blood.
Intrinsic process activates Factor XII.
Both of these processes mainly activate the formation of thrombin.
And in the final result fibrin molecules are released which are helpful for giving firmness to the platelet plug.
Hemostatic response:
Vasospasm:
Vessels become spasmodic suddenly after the vessel is damaged.
Formation of platelet plug:
After the endothelium is damaged the platelets get stick to collagen as well as to each other resulting in the formation of platelet plug.
Several factors are released by platelets such as ADP, TXA2, and serotonin which results in further aggregation of platelets as well as vasoconstriction.
Next in the process, aggregated plug of platelets make it possible for the platelet factor 3 availability leading to the sequence of coagulation process further to take place.
Fibrin reinforcement of platelet plug:
A series of reactions are activated after the stimulation of coagulation system. Coagulation system works through two interrelated processes – Intrinsic and extrinsic processes.
Extrinsic pathway:
Extrinsic denotes something that comes from outside. Extrinsic pathway denotes a series of reactions which is activated by tissue factor that comes from outside of blood.
It activates Factor VII by a tissue factor i.e. thromboplastin
Intrinsic Pathway:
Intrinsic denotes something which is found in body part. In the intrinsic pathway proteins for the activation of the process of blood coagulation are present in the blood.
Intrinsic process activates Factor XII.
Both of these processes mainly activate the formation of thrombin.
And in the final result fibrin molecules are released which are helpful for giving firmness to the platelet plug.
Thursday, March 31, 2011
Imipramine
It is an anti-arrhythmic drug and belongs to class IA of drugs.
Action:
It inhibits the reuptake of serotonin and norepinephrine.
Uses:
It is an anti-arrhythmic drugs and is also used in depression and enuresis in children aged 6 years.
Action:
It inhibits the reuptake of serotonin and norepinephrine.
Uses:
It is an anti-arrhythmic drugs and is also used in depression and enuresis in children aged 6 years.
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Tuesday, March 29, 2011
Worldwide Cancer Status
Cancer is found to be the leading cause of death in the world with the 13% of all death cases around the world in 2008. About 12.7 million cases of cancer and 7.6 million deaths were calculated in 2008. Upto middle-income countries there are about half (51%) of all cancer cases worldwide in 1975; while this proportion increased to 55% in 2007 and is thought to reach 61% by the year 2050.
There are more than 100 types of cancer and it can affect any part of the body.
Two factors are increasing the number of worldwide cancer patients:
1. Aging
2. Cancer causing attitude such as use of tobacco (It is estimated that about 1.3 billion people worldwide smoke tobacco), harmful or damaging use of alcohol, physical inactivity or poor diet
3. Older age
4. Race
5. Family history
Apart from these factors some other factors can also cause cancer such as
1. Over weight and obesity (WHO estimates that in 2005, overweight adults were about 1.6 billion from the total population and 300 million obese. It is estimated that the number of overweight people may go upto 2.3 billion by the year 2015.
2. Exposure to environmental carcinogens such as radon, arsenic, asbestos and polycyclic aromatic hydrocarbons.
3. Chronic Infections
A large number of cancer cases and deaths are in developing countries.More than 70 % of all cancer deaths occured in developing countries.
Breast Cancer is leading type of cancer in females and lung cancer is the leading type of cancer in males, since 1985, and they are also the leading cause of death from cancer for both developing as well as developed world. In females, lung cancer is the fourth most commonly diagnosed cancer and second most important cause of death from cancer. According to 2003-2007 research, top 5 cancer sites are prostate (a gland males that surround the tube for discharging urine located below the bladder), Breast, Lung as well as Bronchus and Colon (part of large intestine) as well as rectum (lower part of the large intestine).
Incidence rates of cancer is twice as high in developed countries as compared to developing countries.
It has been estimated that more than 30% of cancer deaths can be prevented by preventing the use of tobacco, taking a healthy diet, showing physical activity, and by prevention of infections that may cause cancer such as chronic (old) infections of hepatitis B virus (HBV) and/or human papillomavirus (HPV).
References:
Jemal, A.; Bray, F.; Center, M. M.; Ferlay, J.; Ward, E.; Forman, D. 2011. Global cancer statistics. A Cancer Journal for Clinicians, 61, Pages 69-90.
SEER Cancer Statistics Review 1975-2007. 2007. http://seer.cancer.gov/csr/1975_2007/browse_csr.php?section=1&page=sect_01_table.23.html#b . Accessed Mar 30, 2011.
Thun, M. J.; DeLancey, J. O. et al. 2010. The global burden of cancer: priorities for prevention. Carcinogenesis, Volume 31, Issue 1, Pages 100-110.
World Health Organization (WHO), Cancer; Fact Sheet. Feb 2011, http://www.who.int/mediacentre/factsheets/fs297/en/ . Accessed Mar 30, 2011.
There are more than 100 types of cancer and it can affect any part of the body.
Two factors are increasing the number of worldwide cancer patients:
1. Aging
2. Cancer causing attitude such as use of tobacco (It is estimated that about 1.3 billion people worldwide smoke tobacco), harmful or damaging use of alcohol, physical inactivity or poor diet
3. Older age
4. Race
5. Family history
Apart from these factors some other factors can also cause cancer such as
1. Over weight and obesity (WHO estimates that in 2005, overweight adults were about 1.6 billion from the total population and 300 million obese. It is estimated that the number of overweight people may go upto 2.3 billion by the year 2015.
2. Exposure to environmental carcinogens such as radon, arsenic, asbestos and polycyclic aromatic hydrocarbons.
3. Chronic Infections
A large number of cancer cases and deaths are in developing countries.More than 70 % of all cancer deaths occured in developing countries.
Breast Cancer is leading type of cancer in females and lung cancer is the leading type of cancer in males, since 1985, and they are also the leading cause of death from cancer for both developing as well as developed world. In females, lung cancer is the fourth most commonly diagnosed cancer and second most important cause of death from cancer. According to 2003-2007 research, top 5 cancer sites are prostate (a gland males that surround the tube for discharging urine located below the bladder), Breast, Lung as well as Bronchus and Colon (part of large intestine) as well as rectum (lower part of the large intestine).
Incidence rates of cancer is twice as high in developed countries as compared to developing countries.
It has been estimated that more than 30% of cancer deaths can be prevented by preventing the use of tobacco, taking a healthy diet, showing physical activity, and by prevention of infections that may cause cancer such as chronic (old) infections of hepatitis B virus (HBV) and/or human papillomavirus (HPV).
References:
Jemal, A.; Bray, F.; Center, M. M.; Ferlay, J.; Ward, E.; Forman, D. 2011. Global cancer statistics. A Cancer Journal for Clinicians, 61, Pages 69-90.
SEER Cancer Statistics Review 1975-2007. 2007. http://seer.cancer.gov/csr/1975_2007/browse_csr.php?section=1&page=sect_01_table.23.html#b . Accessed Mar 30, 2011.
Thun, M. J.; DeLancey, J. O. et al. 2010. The global burden of cancer: priorities for prevention. Carcinogenesis, Volume 31, Issue 1, Pages 100-110.
World Health Organization (WHO), Cancer; Fact Sheet. Feb 2011, http://www.who.int/mediacentre/factsheets/fs297/en/ . Accessed Mar 30, 2011.
Nitroglycerin
It is also referred to as “Glyceryl trinitrate”.
Mechanism of action:
Intracellularly, Nitroglycerin gives nitrite ions, which then changes into endothelium derived relaxing factor (EDRF) i.e. nitric oxide. This NO then reacts with sulfhydryl (-SH) containing receptors associated with guanylate cyclase resulting in the activation of soluble Guanylate cyclase which promotes cells’ cyclic GMP level, which activates protein kinase G leading to the dephosphorylation of the myosin light chain. This causes ion binding process of Ca2+and at last relaxation of the vascular smooth muscle.
Actions:
It causes a reduced cardiac work resulting in the decreased oxygen demand of the heart muscles.
1. It causes venodilation so that blood is pooled in the veins resulting in the decreased preload and work of the heart.
2. It causes an increased flow of blood to the myocardium by dilating the coronary vessels.
Pharmacokinetics:
Its onset of action is one minute. It undergoes through the first pass metabolism and that is why it is taken sublingually or via transdermal patches.
Therapeutic uses:
Sublingual nitroglycerin is used for immediate relief from angina induced by physical activity or stress.
Mechanism of action:
Intracellularly, Nitroglycerin gives nitrite ions, which then changes into endothelium derived relaxing factor (EDRF) i.e. nitric oxide. This NO then reacts with sulfhydryl (-SH) containing receptors associated with guanylate cyclase resulting in the activation of soluble Guanylate cyclase which promotes cells’ cyclic GMP level, which activates protein kinase G leading to the dephosphorylation of the myosin light chain. This causes ion binding process of Ca2+and at last relaxation of the vascular smooth muscle.
Actions:
It causes a reduced cardiac work resulting in the decreased oxygen demand of the heart muscles.
1. It causes venodilation so that blood is pooled in the veins resulting in the decreased preload and work of the heart.
2. It causes an increased flow of blood to the myocardium by dilating the coronary vessels.
Pharmacokinetics:
Its onset of action is one minute. It undergoes through the first pass metabolism and that is why it is taken sublingually or via transdermal patches.
Therapeutic uses:
Sublingual nitroglycerin is used for immediate relief from angina induced by physical activity or stress.
Nitrites and nitrates
These are nitric and nitrous acid esters of glycerol.
Mechanism of action:
1. Nitrates cause relaxation of the coronary vessels resulting in the decreased constriction of coronary vessels. The decreased constriction of the coronary arteries leads to increased transfusion of blood to the muscles of the heart (improved letting of blood).
2. On the other hand, it promotes dilation of the capacitance veins resulting in the decreased venous return to the heart due to pooled effect of blood in the veins. This decreased venous return to the heart decreases oxygen demand of the muscles of the heart.
CVS:
Relaxation occurs in all segments of vascular system:
1. Less dilation of the arterioles and precapillary sphincters due to reflex responses.
2. They reduces cardiac output.
3. It effects directly on coronary artery tone resisting coronary artery spasm in variant angina.
4. Organonitrates causes relaxation of the arteries resulting in the reduced systemic arterial pressure causing reduced afterload of the heart leading to the reduced cardiac oxygen requirement.
5. Organonitrates causes relaxation of the veins resulting in the reduced preload causing reduced myocardial wall tension leading to reduced myocardial oxygen requirement.
6. Reduced left ventricular end diastolic volume reduces tissue pressure around subendocardial vessels promoted coronary blood flow to this area
Other smooth muscle organs:
Organonitrates have short duration of action on the relaxation of the smooth muscles i.e. esophageal and biliary smooth muscle.
Blood:
Nitrite ion may cause pseudocyanosis and tissue hypoxia.
Therapeutic uses:
1. Stable and unstable angina pectoris
2. Variant angina pectoris
3. Orthopnea and Paroxysmal nocturnal dyspnea
4. Cyanide poisoning
Adverse effects:
Facial flushing (due to cutaneous vasodilation), Severe type of headache (due to vasodilation of cerebral vessels leading to elevated intracranial pressure and headache), Orthostatic hypotension, dizziness, weakness
Mechanism of action:
1. Nitrates cause relaxation of the coronary vessels resulting in the decreased constriction of coronary vessels. The decreased constriction of the coronary arteries leads to increased transfusion of blood to the muscles of the heart (improved letting of blood).
2. On the other hand, it promotes dilation of the capacitance veins resulting in the decreased venous return to the heart due to pooled effect of blood in the veins. This decreased venous return to the heart decreases oxygen demand of the muscles of the heart.
Actions:CVS:
Relaxation occurs in all segments of vascular system:
1. Less dilation of the arterioles and precapillary sphincters due to reflex responses.
2. They reduces cardiac output.
4. Organonitrates causes relaxation of the arteries resulting in the reduced systemic arterial pressure causing reduced afterload of the heart leading to the reduced cardiac oxygen requirement.
5. Organonitrates causes relaxation of the veins resulting in the reduced preload causing reduced myocardial wall tension leading to reduced myocardial oxygen requirement.
Other smooth muscle organs:
Organonitrates have short duration of action on the relaxation of the smooth muscles i.e. esophageal and biliary smooth muscle.
Blood:
Nitrite ion may cause pseudocyanosis and tissue hypoxia.
1. Stable and unstable angina pectoris
2. Variant angina pectoris
3. Orthopnea and Paroxysmal nocturnal dyspnea
4. Cyanide poisoning
Adverse effects:
Facial flushing (due to cutaneous vasodilation), Severe type of headache (due to vasodilation of cerebral vessels leading to elevated intracranial pressure and headache), Orthostatic hypotension, dizziness, weakness
Nadolol
This has a long duration of action.
Therapeutic uses:
1. Hypertension
2. Angina pectoris
3. Cardiac tachyarrhythmias
Therapeutic uses:
1. Hypertension
2. Angina pectoris
3. Cardiac tachyarrhythmias
Implants
This represents the form of radiation therapy or radiotherapy involving placement of radioactive entities inside the body of the patient close to the tumor.
An artificial body part placed in tissues (often to replace missing body parts) with the help of surgery.
An artificial body part placed in tissues (often to replace missing body parts) with the help of surgery.
Fusion protein
Fusion proteins are produced by the combination of two genes or proteins or peptides. They can exist naturally or can be prepared in the laboratory.
PEGylated dosage forms
PEGylated dosage form refers to the attachment of the polythylene glycol polymer chains to a drug concealing the agent from the immune sytem of the body reducing immunogenicity resulting in prolonged circulatory time.
Examples:
PEGylated interferon alpha is in use for the treatment of hepatitis B and C.
PEGylated liposome having doxorubicin is used in the treatment of cancer.
Examples:
PEGylated interferon alpha is in use for the treatment of hepatitis B and C.
PEGylated liposome having doxorubicin is used in the treatment of cancer.
Ophthalmic Inserts
Ophthalmic inserts are solid or semisolid sterile preparations for placement in the conjunctival sac of the eye. These are sustained release drug delivery systems for the eye.
Osmotic Systems
Osmotic systems make use of osmotic pressure for controlled delivery of active ingredients.
This method can be used both for systemic and targeted drug delivery.
Mechanism:
Osmotic pressure as a result of imbibitions of the fluid by the osmotic agents directly affects the rate of drug delivery from osmotic systems such as osmotic pumps.
Components of Osmotic Pump:
1. Drug
2. Osmotic agent or osmogent such as magnesium sulfate, sodium chloride or sodium bicarbonate
3. Semipermeable membrane
4. Plasticizers such as polyethylene glycols, triethyl citrate or ethylene glycol monoacetate
Factors affecting Osmotic drug delivery:
1. Size of the opening of delivery point
2. Solubility of the components
3. Intrinsic character of the rate controlling membrane
4. Osmotic pressure of the components
These factors are important to develop an optimized and desired osmotic system.
This method can be used both for systemic and targeted drug delivery.
Mechanism:
Osmotic pressure as a result of imbibitions of the fluid by the osmotic agents directly affects the rate of drug delivery from osmotic systems such as osmotic pumps.
Components of Osmotic Pump:
1. Drug
2. Osmotic agent or osmogent such as magnesium sulfate, sodium chloride or sodium bicarbonate
3. Semipermeable membrane
4. Plasticizers such as polyethylene glycols, triethyl citrate or ethylene glycol monoacetate
Factors affecting Osmotic drug delivery:
1. Size of the opening of delivery point
2. Solubility of the components
3. Intrinsic character of the rate controlling membrane
4. Osmotic pressure of the components
These factors are important to develop an optimized and desired osmotic system.
Monday, March 28, 2011
Mucoadhesive system
Mucoadhesion refers to adhesion with with moist lining in the body passages of mammals containing cells which secrete mucus and opens to the external environment.
Mucoadhesive system refers to the adhesion of natural or synthetic polymer and soft tissues of mucous membrane for an extended period. Cross linked polymer device, containing drug, will adhere to biological membrane and will transfer the drug to the body at the given site, decreasing frequency of administration.
Theories of mucoadhesion:
Following theories have been proposed in the mucoadhesion of the drug:
1. The wetting theory
2. The diffusion theory
3. The electronic theory
4. The adsorption theory
5. The cohesive theory
6. The Fracture theory
7. The mechanical theory
Mucoadhesive system refers to the adhesion of natural or synthetic polymer and soft tissues of mucous membrane for an extended period. Cross linked polymer device, containing drug, will adhere to biological membrane and will transfer the drug to the body at the given site, decreasing frequency of administration.
Theories of mucoadhesion:
Following theories have been proposed in the mucoadhesion of the drug:
1. The wetting theory
2. The diffusion theory
3. The electronic theory
4. The adsorption theory
5. The cohesive theory
6. The Fracture theory
7. The mechanical theory
Controlled release microchips
It represents the slow and controlled release of medicaments from microfabricated device. These are the types of small programmable devices.
In this microchip, micrometer scale pumps, valves and flow channels are incorporated or microfabricated into the active devices. Microchip of solid state silicon can be used in this technique. These microchips have following properties:
1. They can store a large amount and number of chemicals or medicaments
2. They have the ability of controlling the time of release of chemicals or medicaments
3. They have the ability of controlling the rate of release of chemicals or medicaments
These microchips have a tiny power supply. The control of microchips are done by remote control, microprocessors and/or biosensors.
The chemical release takes place through electrochemical dissolution of membranes of thin anode covering microreservoirs which are filled with chemicals in the form liquid, solid or gel.
Uses:
This microchip technology has found uses in many areas such as chemical detection, drug delivery, medical diagnostics and combinatorial chemistry.
References:
January 20, 1999. A commentary on the controlled release microchip. http://web.mit.edu/newsoffice/1999/microchipcom.html. Accessed March 28, 2011.
Santini, J. T. Jr.; Cima, M. J.et al. 1999. A controlled-release microchip. Nature, 397, Pages 335-338.
Santini, J. T. Jr.; Richards, A. C. et al. 2000. Microchips as Controlled Drug-Delivery Devices. Wiley-VCH, 39, Pages 2396-2407.
In this microchip, micrometer scale pumps, valves and flow channels are incorporated or microfabricated into the active devices. Microchip of solid state silicon can be used in this technique. These microchips have following properties:
1. They can store a large amount and number of chemicals or medicaments
2. They have the ability of controlling the time of release of chemicals or medicaments
3. They have the ability of controlling the rate of release of chemicals or medicaments
These microchips have a tiny power supply. The control of microchips are done by remote control, microprocessors and/or biosensors.
The chemical release takes place through electrochemical dissolution of membranes of thin anode covering microreservoirs which are filled with chemicals in the form liquid, solid or gel.
Uses:
This microchip technology has found uses in many areas such as chemical detection, drug delivery, medical diagnostics and combinatorial chemistry.
References:
January 20, 1999. A commentary on the controlled release microchip. http://web.mit.edu/newsoffice/1999/microchipcom.html. Accessed March 28, 2011.
Santini, J. T. Jr.; Cima, M. J.et al. 1999. A controlled-release microchip. Nature, 397, Pages 335-338.
Santini, J. T. Jr.; Richards, A. C. et al. 2000. Microchips as Controlled Drug-Delivery Devices. Wiley-VCH, 39, Pages 2396-2407.
Phonophoresis
It represents the use of ultrasound for the delivery of drugs through the skin. Through this process topical application of anti-inflammatory drugs and analgesics can be increased.
Iontophoresis
A therapeutic strategy or technique in which a small amount of electric current is used locally for introduction of of medicine or some other chemicals (heavy metal ions) into the tissues of the body through the skin.
In this process, bipolar electrodes are used to create electric potential and ionized medication is introduced into the body. Moreover, sweat glands temporarily turn off during this procedure.
In this process, bipolar electrodes are used to create electric potential and ionized medication is introduced into the body. Moreover, sweat glands temporarily turn off during this procedure.
Sunday, March 27, 2011
Moxalactam
It is also known as Latamoxef. It is a third generation cephalosporin and is used parenterally.
Uses:It is a active against Enterobacteriaceae. It is used in the treatment of complicated urinary tract infections.
Uses:It is a active against Enterobacteriaceae. It is used in the treatment of complicated urinary tract infections.
Ceftriaxone
It is a third generation cephalosporin and is administered parenterally.
Action:
It inhibits mucopeptide synthesis in the bacterial cell wall.
Uses:
It is used for the treatment of infections of skin, respiratory tract and urinary tract.
Action:
It inhibits mucopeptide synthesis in the bacterial cell wall.
Uses:
It is used for the treatment of infections of skin, respiratory tract and urinary tract.
Ceftizoxime
It is a third generation cephalosporin and is administered parenterally or in the form of suppository.
Action:
It binds to specific penicillin binding protein and inhibits cell wall synthesis.
Uses:
It is effective against susceptible strains of micro-organisms.
Action:
It binds to specific penicillin binding protein and inhibits cell wall synthesis.
Uses:
It is effective against susceptible strains of micro-organisms.
Ceftazidime
It is a third generation cephalosporin and is administered parenterally.
Action:
It binds to specific penicillin binding protein and inhibits cell wall synthesis.
Uses:It is used to treat infections caused by Pseudomonas and other gram negative infections.
Action:
It binds to specific penicillin binding protein and inhibits cell wall synthesis.
Uses:It is used to treat infections caused by Pseudomonas and other gram negative infections.
Cefotaxime
It is a third generation cephalosporin. It is administered parenterally.
Action:
It binds to specific penicillin binding proteins in the cell wall of bacteria and inhibits bacterial cell wall synthesis.
Uses:It is used to treat infections of meningitis, gonorhoea and infections of the kidney.
Action:
It binds to specific penicillin binding proteins in the cell wall of bacteria and inhibits bacterial cell wall synthesis.
Uses:It is used to treat infections of meningitis, gonorhoea and infections of the kidney.
Cefoperazone
It is a third generation cephalosporin. It is administered parenterally.
Action:
It binds to specific penicillin binding proteins and inhibits cell wall synthesis.
Uses:It is especially used for the treatment of infections caused by the species of Pseudomonas.
Action:
It binds to specific penicillin binding proteins and inhibits cell wall synthesis.
Uses:It is especially used for the treatment of infections caused by the species of Pseudomonas.
Cefixime
It is a third generation cephalosporin and is administered parenterally.
Action:
It inhibits cell wall synthesis by binding to penicillin binding proteins.
Uses:
It is used to treat uncomplicated urinary tract infections and otitis media.
Action:
It inhibits cell wall synthesis by binding to penicillin binding proteins.
Uses:
It is used to treat uncomplicated urinary tract infections and otitis media.
Cefmenoxime
It is a third generation cephalosporin.
Action:
It binds to penicillin binding protein and inhibits bacterial protein synthesis.
Uses:It is effectively used to treat obstetric and gynecologic infections.
Action:
It binds to penicillin binding protein and inhibits bacterial protein synthesis.
Uses:It is effectively used to treat obstetric and gynecologic infections.
Cefetamet
It is a third generation cephalosporin.
Uses:It is active against Enterobacteriacae, streptococci and haemophilis.
Uses:It is active against Enterobacteriacae, streptococci and haemophilis.
Cefsulodin
It is a 3rd generation cephalosporin.
Uses:It is used to treat infections caused by P. aeruginosa.
Uses:It is used to treat infections caused by P. aeruginosa.
Cefpiramide
It is a 3rd generation cephalosporin.
Action:
It binds to penicillin binding protein.
Uses:It is effective against infections caused by P. aeruginosa.
Action:
It binds to penicillin binding protein.
Uses:It is effective against infections caused by P. aeruginosa.
Cefpimizole
It is a third generation cephalosporin. It is a semisynthetic antibiotic and is used parenterally.
Latamoxef
It is a third generation cephalosporin and is a beta lactam antibiotic.
Action:
It inhibits bacterial cell wall synthesis.
Uses:
It is used to treat infections of meninges, urinary tract and gastrointestical tract.
Action:
It inhibits bacterial cell wall synthesis.
Uses:
It is used to treat infections of meninges, urinary tract and gastrointestical tract.
Ceftibuten
It is a 3rd generation cephalosporin. It is administered orally.
Action:
It inhibits bacterial cell wall synthesis.
Uses:
It is used to treat chronic bronchitis, pharyngitis and tonsilitis.
Action:
It inhibits bacterial cell wall synthesis.
Uses:
It is used to treat chronic bronchitis, pharyngitis and tonsilitis.
Cefpodoxime
It is a third generation cephalosporin.
Action:
It binds to penicillin binding protein and results in inihibition of cell wall synthesis.
Uses:
It is used for upper and lower respiratory tract infections and urinary tract infections.
Action:
It binds to penicillin binding protein and results in inihibition of cell wall synthesis.
Uses:
It is used for upper and lower respiratory tract infections and urinary tract infections.
Cefodizime
It is a third generation cephalosporin. It is used parenterally.
Uses:It is used for respiratory tract infections and urinary tract infections.
Uses:It is used for respiratory tract infections and urinary tract infections.
Cefditoren
It is a 3rd generation cephalosporin.
Action:
It acts on penicillin binding protein and results in inhibition of cell wall synthesis.
Uses:
It is used for community acquired pneumonia, chronic bronchitis and pharyngitis.
Action:
It acts on penicillin binding protein and results in inhibition of cell wall synthesis.
Uses:
It is used for community acquired pneumonia, chronic bronchitis and pharyngitis.
Cefdinir
It is a 3rd generation cephalosporin.
Action:It acts on penicillin binding proteins resulting in the inhibition of bacterial cell wall synthesis.
Uses:
It is effective in the treatment of common infections of bacteria such as that of ear, throat and sinus.
Action:It acts on penicillin binding proteins resulting in the inhibition of bacterial cell wall synthesis.
Uses:
It is effective in the treatment of common infections of bacteria such as that of ear, throat and sinus.
Cefcapene
It is 3rd generation cephalosporin.
Action:
It is a beta-lactamase inhibitor.
Uses:It is used to treat chronix respiratory tract infections.
Action:
It is a beta-lactamase inhibitor.
Uses:It is used to treat chronix respiratory tract infections.
Loracarbef
It is a second generation cephalosporin and is administered parenterally.
Action:
It is a beta lactam antibiotic and works by binding to penicillin binding proteins.
Uses:It is used for bacterial infections, pneumonia, pharyngitis and urinary tract infections.
Action:
It is a beta lactam antibiotic and works by binding to penicillin binding proteins.
Uses:It is used for bacterial infections, pneumonia, pharyngitis and urinary tract infections.
Cefuroxime
It is a second generation cephalosporin and is administered parenterally.
Action:
It is a beta lactam antibiotic and works after binding to penicillin binding protein.
Uses:
It is used for both of the gram positive and gram negative organisms and is helpful in the treatment of gonorhea and haemophilus.
Action:
It is a beta lactam antibiotic and works after binding to penicillin binding protein.
Uses:
It is used for both of the gram positive and gram negative organisms and is helpful in the treatment of gonorhea and haemophilus.
Cefprozil
It is a second generation cephalosporin and is administered parenterally.
Action:
It is a beta lactam antibiotic and it works after binding with penicillin binding proteins.
Uses:
It is used to treat bronchitis, skin infections and other bacterial infections.
Action:
It is a beta lactam antibiotic and it works after binding with penicillin binding proteins.
Uses:
It is used to treat bronchitis, skin infections and other bacterial infections.
Cefotetan
It is a second generation cephalosporin and is administered parenterally.
Action:
It caused inhibition of cell wall synthesis of the bacteria by binding and inhibiting the penicllin binding proein.
Uses:
It is active against a wide range of aerobic and anaerobic, gram positive and gram negative micro-organisms.
Action:
It caused inhibition of cell wall synthesis of the bacteria by binding and inhibiting the penicllin binding proein.
Uses:
It is active against a wide range of aerobic and anaerobic, gram positive and gram negative micro-organisms.
Cefoxitin
It is a second generation cephalosporin and is administered parenterally.
Action:
It inhibits bacterial cell wall synthesis.
Uses:
It is used against infections caused by susceptible bacteria.
Action:
It inhibits bacterial cell wall synthesis.
Uses:
It is used against infections caused by susceptible bacteria.
Ceforanide
It is a second generation cephalosporin and is administered parenterally.
Action:
It causes inhibition of cell wall synthesis.
Uses:
It is used for the infections caused by susceptible bacteria.
Action:
It causes inhibition of cell wall synthesis.
Uses:
It is used for the infections caused by susceptible bacteria.
Cefonicid
It is a second generation cephalosporin and is administered parenterally.
Action:It inhibits cell wall synthesis by binding to penicillin binding proteins.
Uses:It is used for lower respiratory infections, urinary tract infections and soft tissue and bone infections.
Action:It inhibits cell wall synthesis by binding to penicillin binding proteins.
Uses:It is used for lower respiratory infections, urinary tract infections and soft tissue and bone infections.
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