Anti-retroviral agents including abacavir (Ziagen), amprenavir (Agenerase), efavirenz (Sustiva), nelfinavir (Viracept), Nevirapine (Viramune, Viramune XR), Ritonavir (Norvir), and lopinavir/ ritonavir (Kaletra) have been shown to decreased the blood levels of methadone making it necessary to adjust the dose of methadone to prevent narcotic withdrawal effects.
Some drugs that slow the heart rate for example, dofetilide (Tikosyn), procainamide (Pronestyl, Procan-SR), quinidine, and sotalol ((Betapace), as well as laxatives and diuretics that cause low magnesium or low potassium in the body, for example, furosemide (Lasix), can cause rare serious and fatal irregular heartbeats.
Quick GuideDrug Abuse: Prescription and OTC Drugs
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