Det kan medføre forhøjede plasmakoncentrationer af methotrexat og øge risikoen for methotrexat - betingede toksiske reaktioner.
Renal tubular transport of methotrexate may be inhibited by concomitant administration of ciprofloxacin, potentially leading to increased plasma levels of methotrexate and increased risk of methotrexate-associated toxic reactions.