Drug Interaction Report

Additional use of local anesthetics including lidocaine should generally be avoided within 96 hours following administration of BUPivacaine. Because the toxic effects of these medications are additive, using them together requires caution and constant monitoring of vital signs and state of consciousness to prevent serious and potentially life-threatening side effects such as methemoglobinemia (a condition that can deprive tissues and organs of oxygen), central nervous system reactions (e.G., convulsions, unconsciousness, coma, respiratory arrest), and cardiovascular disorders (e.G., low blood pressure, heart block, irregular heart rhythm, cardiac arrest). Patients require immediate medical attention if they develop signs and symptoms of methemoglobinemia such as pale, gray, or blue colored skin (cyanosis); headache; rapid heart rate; shortness of breath; lightheadedness; or fatigue. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Using triamcinolone together with ambenonium may result in severe muscle weakness in patients with myasthenia gravis. If you have been receiving treatment with ambenonium, you may experience increased muscle weakness when triamcinolone is first initiated. Improvement in muscular function may occur gradually. Talk to your doctor if you have any questions or concerns. Your doctor may discontinue ambenonium at least one day before you start taking triamcinolone. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Grapefruit juice may increase the blood levels of lidocaine, which may increase the risk of side effects such as low blood pressure, slow heart rate, irregular heart rhythm, difficulty breathing and convulsions. Cigarette smoking may reduce the blood levels of lidocaine, which may make the medication less effective. It is best to avoid smoking during lidocaine therapy. Consuming cruciferous vegetables (e.G., broccoli, brussels sprouts) may also reduce the blood levels of lidocaine. Talk to a healthcare professional if you have any questions or concerns. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Consumer information for this interaction is not currently available.

MONITOR: Smoking cessation may lead to elevated plasma concentrations and enhanced pharmacologic effects of drugs that are substrates of CYP450 1A2 (and possibly CYP450 1A1) and/or certain drugs with a narrow therapeutic index (e.g., flecainide, pentazocine). One proposed mechanism is related to the loss of CYP450 1A2 and 1A1 induction by polycyclic aromatic hydrocarbons in tobacco smoke; when smoking cessation agents are initiated and smoking stops, the metabolism of certain drugs may decrease leading to increased plasma concentrations. The mechanism by which smoking cessation affects narrow therapeutic index drugs that are not known substrates of CYP450 1A2 or 1A1 is unknown. The clinical significance of this interaction is unknown as clinical data are lacking.

MANAGEMENT: Until more information is available, caution is advisable if smoking cessation agents are used concomitantly with drugs that are substrates of CYP450 1A2 or 1A1 and/or those with a narrow therapeutic range. Patients receiving smoking cessation agents may require periodic dose adjustments and closer clinical and laboratory monitoring of medications that are substrates of CYP450 1A2 or 1A1.