No significant drug interactions have been reported for amlodipine

Dysopyramide clearance may be reduced by 20% by atenolol. This may result in additional inotropic effect. In high doses (1g and above) ampicillin may reduce serum levels of atenolol.

Beta blockers may decrease tissue sensitivity to insulin and inhibit insulin secretion eg. response to sulphonylureas.

Being cardioselective atenolol may be much less active in this regard. It is also likely to cause hypertension during hypoglycaemia.

NSAIDs may reduce the antihyperternsive effect of atenolo.

Hypertension, preventive management of chronic stable angina.

Amlodopine/atenolol combinationis well tolerated.

Side effects include, headache, oedema, depression, dizziness, breathlessness, muscle cramps, fatigue, tiredness, and bradycardia..

Somnolence, chest pain, and impotence may occur rarely.

Hypotension,cardiogenic shock, sinus bradycardia, heart block of second and higher degrees, congestive heart failure, poor L.V. function and hypersensitivity to any of the component.

Special precautions:

Excessive fall in blood pressure may occur in some patients especially elderly. Rarely anginal symptoms may be aggrevated in some patients.

The combination should be used with caution in patients with COPD, hepatic or renal impairment, thyrotoxicosis, congestive failure and vasospatic angina. In diabetes melitus, tachycardia as an indicator of hypoglycaemia may be abolished.

Any withdrawal of this combination should be gradual.

Pregnancy and lactation:

Use of this combination is not recommended. Children- Safety and efficacy of amlodipine in this group has not been established.

Overdose :

Overdose may be indicated by severe hypotension. Gatric lavage and supportive therapy including volume expanders and vasopressers would be required

Indication

Hypertension, preventive management of chrinic stable angina.

Dosage

One tablet once a day

Take with or without food

Pharmacology:

A combination of these products has been shown to be effective in hypertension and angina. Concurrent use of amlodipine and atenolol in patients with angina and/ or hypertension not responding to either drug alone can result in a better clinical response. Amlodipine reduces vascular component while atenolol reduces cardiac factor.

Pharmacokinetics:

No pharmacokinetic interactions have been described between amlodipine and atenolol. Amlodipine is slowly but well absorbed after oral administration with a bioavailability of 64 to 80%. There is no first pass metabolism.

Peak plasma levels are reached in 6- 12 hours. Absorption is not affected by food. Amlodipine is slowly but extensively metabolised in liver into inactive metabolites and excreted in the kidney.

Elimination half life in steady state is 45 hours. No human data are available about amlodipine crossing the placenta or getting excreted into breast milk. Absorption of atenolol from the GI tract is only 40%. First pass metabolism is negligable.

Peak plasma levels are reached in 2-4 hrs. Binding to plasma proteins is about 3- 5%. Atenol crosses into foetal circulation and is excreted into breast milk. Atenolo metabolic clearance is minimal and unchanged drug is exreted thriugh the kidney.

Elimination half life is 6- 7 hrs., which may pronged in renal impairment.

The Canadian Amlodipine/Atenolol in silent Ischaemia Study (CASIS) compared the effects of amlodipine and atenolol during treadmill testing and ambulatory monitoring under randomised double blind conditions.

Ischaemia during testing was supressed by amlodipine more effectively than atenolol. But ischamia during monitoring was suopressed more effectively by atenolol. The combination of these two drugs was more effective than the individual drugs.

Absorption not affected by food.

Take with or without food

Pregnancy and lactation :

Use of this combination is not recommended.

Children-

Safety and efficay of amlodipine in this group has not been established.