Ciprofloxacin and Pentoxifylline interaction
Ciprofloxacin and Pentoxifylline: 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 Ciprofloxacin label · effective 2026-06-30
Serious Adverse Reactions with Concomitant Theophylline Serious and fatal reactions have been reported in patients receiving concurrent administration of ciprofloxacin and theophylline.
If concomitant use cannot be avoided, monitor serum levels of theophylline and adjust dosage as appropriate [see Drug Interactions ( 7 )].
Theophylline Avoid Use (Plasma Exposure Likely to be Increased and Prolonged) Concurrent administration of ciprofloxacin with theophylline may result in increased risk of a patient developing central nervous system (CNS) or other adverse reactions.
If concomitant use cannot be avoided, monitor serum levels of theophylline and adjust dosage as appropriate [see Warnings and Precautions ( 5.10 )].
Interacting Drug Interaction Theophylline Serious and fatal reactions.
From the Pentoxifylline label · effective 2026-05-15
Concomitant administration of strong CYP1A2 inhibitors (including e.g., ciprofloxacin or fluvoxamine) may increase the exposure to pentoxifylline (see ADVERSE REACTIONS).
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.