Bromocriptine

It is available in the salt form of Bromocriptine Mesylate.

Action:
It is a dopamine agonist.
Uses:
It is used in the treatment of Parkinson's disease. It is also used in the treatment of Pituatory tumors, type 2 diabetes and neuroleptic malignant syndrome.

Biperiden

It is available in the salt form of Biperiden Hydrochloride or Biperiden lactate.

Action:
It possesses Anti-cholinergic properties.

Uses:
It is used in the management of Parkinson's disease.

Benztropine

It is available in the form of Benztropine Mesylate.

Action:
It possesses both Anti-cholinergic as well as Anti-histaminic properties. Its anti-cholinergic property is mainly important in the control of Parkinson's disease.
Uses:
It is used in the treatment of Parkinson's Disease.

Apomorphine

It is a derivative of morphine but is less active and work as a dopaminergic agonist.

Mechanism of Action:
It causes an increase in the dopamine amount in brain.
Uses:
It is used as an emetic and in little doses can also be used as sedative. It is also used as an Anti-parkinsonian agent.

Amantadine

It is used in the form of Amantadine Hydrochloride.

Mechanism of Action:
It helps in the treatment of Parkinson's disease by increasing the amount of dopamine in brain.

Uses:
It is an Anti-viral drug, used in the symptomatic or prophylactic treatment of Influenze-A, and is also used in the treatment of Parkinson's Disease.
It may also help in reducing dyskinesias.

Adverse Effects:
It may cause seizures in elderly people when used in high doses.

Atenolol

Therapeutic uses:

1. Hypertension
2. Angina pectoris
3. Cardiac dysarrhythmias

Safe in patients with diabetes or peripheral vascular disease

β-adrenoceptor blockers

Most β-adrenoceptor blockers are reversible and competitive antagonists for β-receptors. β-adrenoceptor blockers are of two types:

Beneficial effects in angina:
1. Through its β-blocking effect, it decreases sympathetic activation (i.e. catecholamine induction) of heart, resulting in

These effects decrease oxygen requirement of the muscles of the heart at rest as well as during physical activity.
2. Reduced heart rate causes an elevated diastolic perfusion time that promotes myocardial perfusion.

Adverse effects in angina:
As the heart rate is decreased, it causes an increased end diastolic volume and promoted ejection time.
This results in increased myocardial oxygen requirement.

Uses of β-blockers:
1. They are useful in classic angina

2. They decrease blood pressure in hypertension
3. They are helpful in cardiac arrhythmias
4. They are helpful in glaucoma
5. They are also helpful in therapy of myocardial infarction
6. Prophylactically helpful for treating migraine headache
It is used synchronously with nitrates to lessen its unwanted effects. On the other hand, this combination is also helpful for promoting duration of exercise as well as tolerance.

Contraindications:
It is contraindicated in patients of:
1. Asthma
2. Peripheral vascular disease
3. Chronic obstructive pulmonary disease
4. Diabetes