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CONTRAINDICATIONS
Patients with known sensitivity to dihydropyridines
DOSAGE AND ADMINISTRATION
For both hypertension and angina, the usual initial dose is 5 mg once daily which maybe increased to a maximum dose of 10 mg depending on
the individual patients response.
No dose adjustment of Vamlo is required upon concomitant administration of thiazide diuretics, beta-blockers and angiotensin-converting enzyme
inhibitors.
Use in the Elderly: Normal dosage regimens are recommended. Amlodipine, used at similar doses in elderly or younger patients, is equally well
tolerated.
Use in Children: Safety and effectiveness of amlodipine in children have not been established.
Use in Patients with Impaired Hepatic Function: As with all calcium antagonists, amlodipine half-life is prolonged in patients with impaired
liver function and dosage recommendations have not been established. The drug should therefore be administered with caution in these patients.
Use in Renal Failure : Amlodipine may be used in such patients at normal doses. Changes in amlodipine plasma concentrations are not
correlated with degree of renal impairment. Amlodipine is not dialyzable.
PRECAUTIONS/WARNINGS/DRUG INTERACTIONS
Use inpatients with Heart Failure: Amlodipine was associated with increased reports of pulmonary oedema despite no significant difference in
the incidence of worsening heart failure as compared to placebo. There are no data to support the use of amlodipine alone, during or within one
month of a myocardial infarction. The safety and efficacy of amlodipine in hypertensive crisis has not been established.
Pregnancy and Lactation
Use in pregnancy & lactation: Safety of Vamlo in human pregnancy or lactation has not been established. Amlodipine does not demonstrate
toxicity in animal reproductive studies other than to delay parturition and prolong labor in rats at a dose level 50 times the maximum
recommended dose in humans. Accordingly, use in pregnancy is only recommended when there is no safer alternative and when the disease
itself carries greater risk for the mother and child.
• Drug Interactions
Amlodipine has been safely administered with thiazide diuretics, alpha blockers, beta blockers, angiotensin-converting enzyme inhibitors, long-
acting nitrates, sublingual glyceryl trinitrate, non-steroidal anti-inflammatory drugs, antibiotics, and oral hypoglycaemic drugs. Amlodipine has
no effect on protein binding of digoxin, phenytoin, warfarin or indomethacin. Effect of other agents on amlodipine: Cimetidine: Co-administration
of amlodipine with cimetidine did not alter the pharmacokinetics of amlodipine. Grapefruit Juice: Co-administration of 240ml of grapefruit juice
with a single oral dose of amlodipine 10mg in 20 healthy volunteers had no significant effect on the pharmacokinetics of amlodipine. Sildenafil:
When amlodipine and sildenafil were used in combination, each agent independently exerted its own blood pressure lowering effect. Effect of
amlodipine on other agents Atorvastatin: Co-administration of multiple 10mg doses of amlodipine with 80mg of atorvastatin resulted in no
significant change in the steady state pharmacokinetic parameters of atorvastatin. Digoxin: Co-administration of amlodipine with digoxin did not
change serum digoxin levels or digoxin renal clearance in normal volunteers. Warfarin: In healthy male volunteers, the co-administration of
amlodipine does not significantly alter the effect of warfarin on prothrombin response time. Cyclosporin: Pharmacokinetic studies with
cyclosporin have demonstrated that amlodipine does not significantly alter the pharmacokinetics of cyclosporin.
SIDE EFFECTS/ADVERSE EFFECTS
Amlodipine is well tolerated. In placebo-controlled clinical trials involving patients with hypertension or angina, the most commonly observed
side effects were headache, edema, fatigue, nausea, flushing and dizziness. Less commonly observed side effects in marketing experience
include pruritus, rash, dyspnea, asthenia, muscle cramps, dyspepsia, gingival hyperplasia and rarely, erythema multiforme. As with other
calcium-channel blockers, the following adverse events have been rarely reported and cannot be distinguished from the natural history of the
underlying disease, e.g. myocardial infarction, arrhythmia (including ventricular tachycardia and atrial fibrillation) and chest pain.
No pattern of clinically significant laboratory test abnormalities related to amlodipine has been observed.
SYMPTOMS AND TREATMENT FOR OVERDOSAGE AND ANTIDOTE(S)
In humans, experience with intentional over dose is limited. Gastric lavage may be worthwhile in some cases. Available data suggest that gross
overdosage could result in excessive peripheral vasodilation with subsequent marked and probably prolonged systemic hypotension. Clinically
significant hypotension due to amlodipine overdosage calls for active cardiovascular support including monitoring of cardiac and respiratory
function, elevation of extremities, and attention to circulating fluid volume and urine output. A vasoconstrictor may be helpful in restoring
vascular tone and blood pressure, provided that there is no contraindication to its use. IV calcium gluconate may be beneficial in reversing the
effects of calcium-channel blockade. Since amlodipine is highly protein-bound, dialysis is not likely to be of benefit.
STORAGE
Store below 25°C, protected from light and moisture.
SHELF LIFE
3 years
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