Interference with smoking-cessation effects of varenicline after administration of immediate-release amphetamine-dextroamphetamine.
An 18-year-old man with attention-deficit-hyperactivity disorder (ADHD) was prescribed varenicline for smoking cessation. He quit smoking after 1 week of therapy and remained smoke free for the next 17 days. During that time, he had also been taking amphetamine-dextroamphetamine (Adderall) on work days for his ADHD. Because his supply of amphetamine-dextroamphetamine was diminishing, he took only half (30 mg every morning) of his prescribed dosage from days 4-12 of varenicline therapy. He further reduced his dosage to 15 mg every morning on days 13 and 14 of varenicline therapy, and his supply of amphetamine-dextroamphetamine was depleted on day 15. On day 23 of varenicline therapy, he received and filled a new prescription for amphetamine-dextroamphetamine and resumed his prescribed dosage (30 mg twice/day). He began smoking again within 48 hours. Rechallenge with varenicline while the patient continued to receive amphetamine-dextroamphetamine yielded similar results. Data suggest that addition of amphetamine to varenicline may negate the partial agonism of varenicline, resulting in elimination of the smoking-cessation aid's benefits. Other potential mechanisms for the drug interaction may also exist. Thus, varenicline may not aid smoking cessation in patients undergoing treatment with amphetamine and amphetamine-like drugs.
Whitley
Heather P
HP
Department of Pharmacy Practice, Auburn University Harrison School of Pharmacy, Tuscaloosa, Alabama, USA. whitlhp@auburn.edu
Moorman
Krystal L
KL
D000293:Adolescent; D000662:Amphetamines / Q000009:adverse effects / Q000627:therapeutic use*; D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy; D001552:Benzazepines / Q000009:adverse effects / Q000627:therapeutic use*; D000697:Central Nervous System Stimulants / Q000009:adverse effects / Q000627:therapeutic use; D003913:Dextroamphetamine / Q000009:adverse effects / Q000627:therapeutic use*; D004338:Drug Combinations; D004347:Drug Interactions; D006801:Humans; D008297:Male; D011810:Quinoxalines / Q000009:adverse effects / Q000627:therapeutic use*; D012008:Recurrence; D012907:Smoking / Q000188:drug therapy; D016540:Smoking Cessation / Q000379:methods*; D013997:Time Factors; D016896:Treatment Outcome; D000068580:Varenicline
D000662:Amphetamines; D001552:Benzazepines; D000697:Central Nervous System Stimulants; D004338:Drug Combinations; D011810:Quinoxalines; D003913:Dextroamphetamine; D000068580:Varenicline