Interactions : אינטראקציות

4.5.   Interaction with other medicinal products and other forms of interaction
Bacteriostatic antibiotics given concurrently with cloxacillin might decrease the bacteriocidal effect of penicillins as it has been shown in vitro. Nevertheless, the clinical significance of this interaction is not well documented.
Beta-adrenergic blockers given with cloxacillin can induce anaphylactic reactions that would make it even more difficult to treat anaphylaxis due to allergic reaction.
Chloramphenicol and cloxacillin co-administration would result to weaken the penicillin’s effect and to increase the half-life of chloramphenicol.
Oral anticoagulants or heparin administrated in conjunction with high dosage of IV penicillins turn the anticoagulants agents less effective and possibly increase the risk of bleeding.
Probenecid tends to block the renal tubular secretion of penicillins and in consequence penicillins stays longer in the blood circulation.
Oral contraceptives and concomitant use of penicillins has been related with unintended pregnancies and menstrual changes. The reason being that penicillins interfere with the absorption of oral contraceptives.