Acetazolamide and Butalbital, aspirin, caffeine, and codeine interaction
Acetazolamide and Butalbital, aspirin, caffeine, and codeine: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Acetazolamide label · effective 2026-01-23
Caution is advised for patients receiving concomitant high-dose aspirin and acetazolamide, as anorexia, tachypnea, lethargy, metabolic acidosis, coma, and death have been reported.
Acetazolamide decreases urinary excretion of amphetamine and may enhance the magnitude and duration of their effect.
DRUG INTERACTIONS Aspirin - See WARNINGS .
From the Butalbital, aspirin, caffeine, and codeine (BUTALBITAL, ASPIRIN, CAFFEINE and CODEINE PHOSPHATE) label · effective 2026-01-15
Examples: Acetazolamide, methazolamide Methotrexate Clinical Impact: Aspirin may enhance the toxicity of methotrexate by displacing it from its plasma protein binding sites and/or reducing its renal clearance.
Diuretics Clinical Impact: Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Intervention: Evaluate patients for signs of diminished diuresis and/or effects on blood pressure and increase the dosage of the diuretic as needed.
The effectiveness of diuretics in patients with underlying renal or cardiovascular disease may be diminished by the concomitant administration of aspirin due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Examples: Probenecid Carbonic Anhydrase Inhibitors Clinical Impact: Concurrent use with aspirin can lead to high serum concentrations of the carbonic anhydrase inhibitor and cause toxicity due to competition at the renal tubule for secretion.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.