Bupivacaine drug interactions

A drug interaction has been identified between the antimycotic agent itraconazole and bupivacaine enantiomers. Coadministration of itraconazole orally with intravenous bupivacaine caused the clearance of both bupivacaine enantiomers to decrease by 25% [214]. This interaction is of concern for the drug, since the R enantiomer has been linked with the development of cardiac arrhythmias. 

Drug interactions administration of DepoDur after an analgesic dose of bupivacaine (0.25% - 20 mL) increases peak serum concentrations of morphine. Increasing the interval between the analgesic dose and DepoDur administration to greater than 30 minutes minimizes this pharmacokinetic interaction. 

Drug interactions intravenous administration of a benzodiazepine will provide sedation and hypnosis for patient comfort during anesthetic procedures and also serve to raise the seizure threshold, thus minimizing the adverse CNS affect of bupivacaine. 

Drug interactions bupivacaine solutions containing epinephrine or norepinephrine administered to patients receiving monoamine oxidase inhibitors or tri-cychc antidepressants may produce severe, prolonged hypertension. Concurrent administration of vasopressor drugs added to bupivacaine/vasoconstrictor solutions and of ergot-type oxytocic drugs may cause severe, persistent hypertension or cerebrovascular accidents. 

In small doses, local anesthetics can depress posttetanic potentiation via a prejunctional neural effect. In large doses, local anesthetics can block neuromuscular transmission. With higher doses, local anesthetics block acetylcholine-induced muscle contractions as a result of blockade of the nicotinic receptor ion channels. Experimentally, similar effects can be demonstrated with sodium channel-blocking antiarrhythmic drugs such as quinidine. However, at the doses used for cardiac arrhythmias, this interaction is of little or no clinical significance. Higher concentrations of bupivacaine (0.75%) have been associated with cardiac arrhythmias independent of the muscle relaxant used. 

Ghoneim MM, Pandya H. Plasma protein binding of bupivacaine and its interaction with other drugs in man. Br J Anaesth 1974 46(6) 435-8. 

Denson DD, Myers JA, Coyle DE. The clinical relevance of the drug displacement interaction between meperidine and bupivacaine. Res Commun Chem Pathol Pharmacol 1984 45(3) 323-30. 

Mixtures of local anaesthetics are sometimes used to exploit the most useful characteristics of each drug. This normally seems to be safe although it is sometimes claimed that it increases the risk of toxicity. There is a case report of a man who developed toxicity when bupivacaine and mepivacaine were mixed together. Spinal bupivacaine followed by epidural ropivacaine may also interact to produce profound motor blockade. However, the effectiveness of bupivacaine in epidural anaesthesia may be reduced if it is preceded by chloroprocaine. 

The magnitude of the upheld shifts in proton resonances when the free base of bupivacaine served as the tt donor were 0.0662 and 0.2513 ppm, indicating that interaction between the drug and DNB was stronger than between DMAC and DNB. Measurements of the therapeutically administered hydrochloride salt of bupivacaine as tt donor, mixed with DNB in 50/50 D2O/CD3CN,... 

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