Veral Overdosage

Symptoms: The symptoms of intoxication after intoxications with verapamil hydrochloride depend on the quantity supplied, the time of detoxification measures and myocardial contractility (age-dependent).
The following symptoms are observed in case of severe intoxication with verapamil: Considerable fall in blood pressure, cardiac insufficiency, bradycardiac or tachycardiac arrhythmias (e.g. junctional rhythm with AV dissociation and higher-degree AV block) which can lead to cardiovascular shock and cardiac arrest.
Depression of consciousness up to coma, hyperglycaemia, hypokalaemia, metabolic acidosis, hypoxia, cardiogenic shock with pulmonary oedema, impaired renal function and convulsions, deaths have uncommonly been reported.
Therapeutic measures: Elimination of the noxae and restoration of stable cardiovascular conditions have therapeutic priority.
The therapeutic measures depend on the time and mode of administration as well as on the type and severity of the intoxication symptoms.
In case of intoxications with high amounts of retard preparations, it has to be taken into account that the substance may still be released and absorbed in the intestine for more than 48 hours after intake.
Gastric lavage is to be recommended after oral intoxication with verapamil hydrochloride, even later than 12 hours after intake if no gastrointestinal motility (bowel sounds) can be detected. In case of suspected intoxication with retard preparations, extensive elimination measures are indicated, such as induced vomiting, removal of the contents of stomach and small intestine via suction while monitoring endoscopically, intestinal lavage, laxation, high enema.
Haemodialysis is not useful, since verapamil hydrochloride is not dialysable; however, haemofiltration and possibly plasmapheresis are recommended (high plasma protein binding of calcium antagonists).
Usual intensive care resuscitative measures, such as extrathoracic cardiac massage, ventilation, defibrillation or pace-maker therapy.
Specific measures: Removal of cardiodepressive effects of hypotension and bradycardia: Bradycardiac arrhythmias are to be treated symptomatically with atropine and/or beta-sympathomimetics (isoprenaline, orciprenaline); alarming cases of bradycardiac arrhythmias require temprary pace-maker therapy.
Asystoles should be handled by the usual measures including beta adrenergic stimulation (e.g., isoprenaline).
Calcium is a specific antidote, e.g. 10-20 ml of a 10% calcium gluconate solution administered intravenously (2.25 to 4.5 mmol), if necessary repeated or as continuous instillation (e.g. 5 mmol/hour).
Hypotension resulting from cardiogenic shock and arterial vasodilation is to be treated with dopamine (up to 25 μg per kg bodyweight per minute), dobutamine (up to 15 μg per kg bodyweight per minute), epinephrine or norepinephrine, respectively. The dose of these medicinal agents is oriented solely to the achieved effect. The serum calcium level should be maintained at a highly normal to slightly elevated level. Due to arterial vasodilation, liquid is additionally substituted in the early phase (Ringer's solution or sodium chloride solution).