Naropin Drug Interactions

Naropin should be used with caution in patients receiving other local anaesthetics or agents structurally related to amide-type local anaesthetics e.g. certain antiarrhythmics such as lidocaine and mexiletine since the systemic toxic effects are additive. Specific interaction studies with ropivacaine and anti-arrhythmic drugs class III (e.g. amiodarone) have not been performed, but caution is advised. (See Precautions.)
In healthy volunteers, ropivacaine clearance was reduced by up to 77% during co-administration of fluvoxamine, a potent competitive inhibitor of P4501A2.
CYP1A2 is involved in the formation of 3-hydroxy-ropivacaine, a major metabolite. Thus, strong inhibitors of CYP1A2, such as fluvoxamine and enoxacin, given concomitantly with Naropin, can cause metabolic interaction leading to an increased ropivacaine plasma concentration. Prolonged administration of ropivacaine should therefore be avoided in patients treated with strong inhibitors of CYP1A2 such as fluvoxamine and enoxacin (see Precautions).