Interactions : אינטראקציות

4.5 Interaction with other medicinal products and other forms of interaction

Other potentially nephrotoxic or ototoxic medications
Concomitant or sequential administration of vancomycin and other potentially ototoxic or nephrotoxic medicinal products may increase the ototoxicity or nephrotoxicity. Nephrotoxic medicinal products may include iodine-containing contrast media, aminoglycoside antibiotics, platinum-based chemotherapy agents, methotrexate at high doses, piperacilline/tazobactam and some antiviral drugs such as pentamidine, foscarnet, aciclovir, ganciclovir, famciclovir, valaciclovir, valganciclovir, ciclosporin or tacrolimus (see section 4.4). Aminoglycoside 
antibiotics, platinum-based chemotherapy agents and some diuretics could be ototoxic drugs.
The patient should be closely monitored, especially in case of concomitant administration of aminoglycoside antibiotics. The maximum dose of vancomycin will be restricted to 500 mg every 8 hours.



Anaesthetics
It has been reported that the incidence of possible adverse drug reactions (e.g. hypotension, skin flushing, erythema, urticaria, myocardial depression or pruritus) increases when vancomycin is administered concurrently with anaesthetics. To prevent these adverse drug reactions, vancomycin should be administered at least 60 minutes before anaesthetic induction (see section 4.4).

Muscle relaxants
If vancomycin hydrochloride is administered during or immediately after surgery, the effects of the muscle relaxants administered concurrently (in particular succinylcholine), such as neuromuscular blockade may be enhanced or prolonged.

Oral anticoagulants
Concomitant administration of vancomycin and warfarin may increase the effects of the anticoagulants. Numerous cases of increased oral anticoagulants activity have been reported in patients receiving antibiotics. A marked infectious or inflammatory context, age and general condition of the patient appear to be risk factors. Under these circumstances, it is difficult to distinguish between the infectious disease and its treatment in the onset of the INR imbalance. It is recommended to monitor INR frequently during and rapidly after concomitant administration of vancomycin with oral anticoagulants.

Paediatric population
Interaction studies have only been performed in adults.

Special problems of INR imbalance
Numerous cases of increase in the activity of oral anticoagulants have been reported in patients treated with antibiotics. A marked infectious or inflammatory context, the age and the patient’s general condition appear as risk factors. Under these circumstances, it would seem difficult to differentiate between the infectious pathology and its treatment in the appearance of the INR imbalance. However, certain antibiotic classes are more deeply involved: particularly fluoroquinolones, macrolides, cyclins, cotrimoxazole and some cephalosporins.