Can You Take Trimethoprim with Alcohol?
Last reviewed: · Source: US FDA drug label database
Avoid alcohol with trimethoprim — it impairs your immune system while you are fighting a UTI and may worsen nausea.
Is it safe to take Trimethoprim with Alcohol?
Trimethoprim is a commonly prescribed antibiotic for urinary tract infections (UTIs). There is no severe direct pharmacological interaction with alcohol, but alcohol impairs the immune response at exactly the time your body needs to fight the infection. It also worsens common side effects of trimethoprim including nausea and dizziness, and promotes dehydration, which is counterproductive when treating a UTI (drinking plenty of water is important).
How do Trimethoprim and Alcohol interact?
Trimethoprim inhibits dihydrofolate reductase in bacteria. Its metabolism involves CYP2C8 and renal excretion. Alcohol does not significantly alter trimethoprim pharmacokinetics. The concerns are indirect: alcohol impairs neutrophil and T-cell function (immune suppression), dehydrates (counterproductive for UTI treatment), and worsens GI side effects.
Data sourced from the US Food and Drug Administration (FDA) drug label database: OpenFDA trimethoprim drug label.
Who should be careful?
Anyone with a UTI being treated with trimethoprim — particularly important to stay well-hydrated.
What if I've already taken Trimethoprim and Alcohol?
No immediate medical concern. Drink plenty of water and complete the antibiotic course.
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Frequently Asked Questions
Can I drink alcohol on trimethoprim?
Best avoided. Alcohol impairs your immune system, promotes dehydration (bad for UTIs), and may worsen nausea from trimethoprim.
Can I have a drink on antibiotics for a UTI?
Better to avoid it. Alcohol and UTIs do not mix well — alcohol irritates the bladder and urethra, impairs immunity, and promotes dehydration that slows recovery.
Does alcohol make a UTI worse?
Yes. Alcohol is a bladder irritant, impairs immune function, and causes dehydration — all of which can worsen UTI symptoms and slow recovery.
What drinks should I avoid during a UTI?
Alcohol, coffee, and fizzy drinks all irritate the bladder and should be avoided. Drink plenty of water and unsweetened cranberry juice.