Amvasc Plus Overdosage

Amlodipine: Overdosage might be expected to cause excessive peripheral vasodilation with marked hypotension and possibly a reflex tachycardia.
If massive overdose should occur, active cardiac and respiratory monitoring should be given. Frequent blood pressure measurements are necessary. Cardiovascular support including elevation of the extremities and the judicious administration of fluids should be initiated should hypotension occur. If hypotension remains unresponsive to these conservative measures, administration of vasopressors eg, phenylephrine should be considered with attention to circulation volume and urine output. Intravenous calcium gluconate may help to reverse the effects of calcium entry blockade. Hemodialysis is not likely to be of benefit since amlodipine is highly protein bound.
Hydrochlorothiazide: The most common signs and symptoms of HCTZ overdose include electrolyte imbalance (hypokalemia, hypochloremia, hyponatremia) and dehydration resulting from excessive diuresis. Other features of overdose are lethargy, nausea and weakness. Lethargy may progress to coma within a few hours with minimal depression of respiratory and cardiovascular function without evidence of dehydration or serum electrolyte changes. Gastrointestinal irritation and hypermotility may occur, and temporary elevation of blood urea nitrogen has been reported.
In the treatment of thiazide overdosage, gastric contents may be evacuated taking caution to avoid aspiration, particularly in unconscious patients. If the patient is conscious, induction of vomiting with ipecac syrup is effective in removing the drug from the stomach. Do not administer cathartics since they tend to promote loss of fluid and electrolytes. Treatment is generally supportive. Monitor serum electrolyte and renal function. Replacement of fluid and electrolytes may be indicated. Measures may be required to maintain respiratory, cardiovascular and renal function. Gastrointestinal irritation is usually of short duration but may be treated symptomatically. The degree to which HCTZ is removed by hemodialysis has not been established.