Tarka Dosage

The recommended usual dosage range of trandolapril for hypertension is 1 to 4 mg per day administered in a single dose or two divided doses. The recommended usual dosage range of Isoptin-SR for hypertension is 120 to 480 mg per day administered in a single dose or two divided doses.

The hazards (see WARNINGS) of trandolapril are generally independent of dose; those of verapamil are a mixture of dose-dependent phenomena (primarily dizziness, AV block, constipation) and dose-independent phenomena, the former much more common than the latter. Therapy with any combination of trandolapril and verapamil will thus be associated with both sets of dose-independent hazards. The dose-dependent side effects of verapamil have not been shown to be decreased by the addition of trandolapril nor vice versa.

Rarely, the dose-independent hazards of trandolapril are serious. To minimize dose-independent hazards, it is usually appropriate to begin therapy with TARKA only after a patient has either (a) failed to achieve the desired antihypertensive effect with one or the other monotherapy at its respective maximally recommended dose and shortest dosing interval, or (b) the dose of one or the other monotherapy cannot be increased further because of dose-limiting side effects.

Clinical trials with TARKA have explored only once-a-day doses. The antihypertensive effect and or adverse effects of adding 4 mg of trandolapril once-a-day to a dose of 240 mg Isoptin-SR administered twice-a-day has not been studied, nor have the effects of adding as little of 180 mg Isoptin-SR to 2 mg trandolapril administered twice-a-day been evaluated. Over the dose range of Isoptin-SR 120 to 240 mg once-a-day and trandolapril 0.5 to 8 mg once-a-day, the effects of the combination increase with increasing doses of either component.