Drug Interactions between Chantix and Fastin
This report displays the potential drug interactions for the following 2 drugs:
- Chantix (varenicline)
- Fastin (phentermine)
Interactions between your drugs
No interactions were found between Chantix and Fastin. However, this does not necessarily mean no interactions exist. Always consult your healthcare provider.
Chantix
A total of 65 drugs are known to interact with Chantix.
- Chantix is in the following drug classes: cholinergic agonists, smoking cessation agents.
- Chantix is used to treat Smoking Cessation.
Fastin
A total of 196 drugs are known to interact with Fastin.
- Fastin is in the following drug classes: anorexiants, CNS stimulants.
- Fastin is used to treat Weight Loss (Obesity/Overweight).
Drug and food interactions
phentermine food
Applies to: Fastin (phentermine)
GENERALLY AVOID: Alcohol may potentiate the central nervous system and cardiovascular effects of centrally-acting appetite suppressants. In one study, concurrent administration of methamphetamine (30 mg intravenously) and ethanol (1 gm/kg orally over 30 minutes) increased heart rate by 24 beats/minute compared to methamphetamine alone. This increases cardiac work and myocardial oxygen consumption, which may lead to more adverse cardiovascular effects than either agent alone. Subjective effects of ethanol were diminished in the eight study subjects, but those of methamphetamine were not affected. The pharmacokinetics of methamphetamine were also unaffected except for a decrease in the apparent volume of distribution at steady state.
MANAGEMENT: Concomitant use of centrally-acting appetite suppressants and alcohol should be avoided if possible, especially in patients with a history of cardiovascular disease. Patients should be counselled to avoid hazardous activities requiring complete mental alertness and motor coordination until they know how these agents affect them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities.
References (3)
- Mendelson J, Jones RT, Upton R, Jacob P 3rd (1995) "Methamphetamine and ethanol interactions in humans." Clin Pharmacol Ther, 57, p. 559-68
- (2001) "Product Information. Didrex (benzphetamine)." Pharmacia and Upjohn
- (2012) "Product Information. Suprenza (phentermine)." Akrimax Pharmaceuticals
varenicline food
Applies to: Chantix (varenicline)
GENERALLY AVOID: Varenicline may enhance the effects of alcohol as well as alter the way an individual reacts to alcohol. During postmarketing use, some patients have reported experiencing increased intoxicating effects of alcohol while taking varenicline. In addition, some reported cases of neuropsychiatric events, including unusual and sometimes aggressive behavior directed toward oneself or others, may have been worsened by concomitant use of alcohol. These events were often accompanied by amnesia.
MANAGEMENT: Patients should be advised to limit their consumption of alcohol until they know whether varenicline affects their tolerance for alcohol, and to exercise caution driving or operating machinery until they know how quitting smoking and/or varenicline may affect them. Patients should immediately stop taking varenicline and contact their physician if they develop agitation, hostility, aggressive behavior, depressed mood, or changes in behavior or thinking that are not typical for them, or if they develop suicidal ideation or behavior.
References (2)
- (2006) "Product Information. Chantix (varenicline)." Pfizer U.S. Pharmaceuticals Group
- FDA. U.S. Food and Drug Administration (2015) Drug Safety Communications: FDA updates label for stop smoking drug Chantix (varenicline) to include potential alcohol interaction, rare risk of seizures, and studies of side effects on mood, behavior, and thinking. Safety announcement. http://www.fda.go
Therapeutic duplication warnings
No warnings were found for your selected drugs.
Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.
See also
Drug Interaction Classification
Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. | |
Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. | |
Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan. | |
No interaction information available. |
Further information
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
Check Interactions
To view an interaction report containing 4 (or more) medications, please sign in or create an account.
Save Interactions List
Sign in to your account to save this drug interaction list.