Metronidazoleinteractions

Disulfiram: Psychotic reactions can occur in patients who are using LIKMEZ and disulfiram concurrently. Alcohol or Other Products Containing Propylene Glycol: Abdominal cramps, nausea, vomiting, headaches, and flushing can occur in patients who are using LIKMEZ and alcohol or other products containing propylene glycol concurrently. Warfarin and Other Oral Anticoagulants: LIKMEZ can potentiate the anticoagulant effect. Carefully monitor prothrombin time and International Normalized Ratio (INR).

Lithium: Increased lithium serum concentrations; measure serum lithium and serum creatinine concentrations during therapy.

Busulfan: Increased busulfan serum concentrations; avoid concomitant use, monitor for plasma concentrations and adjust the busulfan dose accordingly. CYP Inducers and CYP Inhibitors: Prolonged or accelerated half-life of metronidazole or concomitant medications. Drugs with the Potential for Prolonging the QT Interval: QT prolongation when used with LIKMEZ Interference with Laboratory Tests: Metronidazole may interfere with certain serum chemistry laboratory values

7.1 Disulfiram

Psychotic reactions have been reported in alcoholic patients who are using metronidazole and disulfiram concurrently. LIKMEZ is contraindicated in patients who have taken disulfiram within the last two weeks.

7.2 Alcoholic

Beverages LIKMEZ is contraindicated in patients who consume alcohol or products containing propylene glycol during and for at least 3 days after therapy with LIKMEZ. Use of LIKMEZ with alcohol or other products containing propylene glycol is associated with a disulfiram-like reaction (abdominal cramps, nausea, vomiting, headaches, and flushing).

7.3 Warfarin and other

Oral Anticoagulants Metronidazole has been reported to potentiate the anticoagulant effect of warfarin and other oral coumarin anticoagulants, resulting in a prolongation of prothrombin time. When LIKMEZ is prescribed for patients on this type of anticoagulant therapy, prothrombin time and INR should be carefully monitored.

7.4 Lithium

In patients stabilized on relatively high doses of lithium, short-term use of LIKMEZ has been associated with elevation of serum lithium concentrations and signs of lithium toxicity due to the interaction between metronidazole and lithium. Monitor serum lithium and serum creatinine concentrations for several days after beginning treatment with LIKMEZ to detect any increase that may precede clinical symptoms of lithium toxicity.

7.5 Busulfan

Metronidazole has been reported to increase plasma concentrations of busulfan, which can result in an increased risk for serious busulfan toxicity. Do not administer LIKMEZ concomitantly with busulfan unless the benefit outweighs the risk. If no therapeutic alternatives to LIKMEZ are available, and concomitant administration with busulfan is medically needed, monitor for busulfan plasma concentrations and adjust the busulfan dose accordingly.

7.6 Inhibitors of CYP450

Liver Enzymes The simultaneous administration of LIKMEZ and drugs that decrease microsomal liver enzymes, such as cimetidine, may prolong the half-life and decrease plasma clearance of metronidazole.

7.7 Inducers of CYP450

Liver Enzymes The simultaneous administration of LIKMEZ and drugs that induce microsomal liver enzymes, such as phenytoin or phenobarbital, may accelerate the elimination of metronidazole, resulting in reduced plasma concentrations of metronidazole. Impaired clearance of phenytoin has also been reported.

7.8 Drugs that

Prolong the QT Interval QT prolongation has been reported, particularly when metronidazole was administered with drugs with the potential for prolonging the QT interval.

7.9 Drug/Laboratory

Test Interactions Metronidazole may interfere with certain types of determinations of serum chemistry values, such as aspartate aminotransferase (AST, SGOT), alanine aminotransferase (ALT, SGPT), lactate dehydrogenase (LDH), triglycerides, and glucose hexokinase. Values of zero may be observed. All of the assays in which interference has been reported involve enzymatic coupling of the assay to oxidation-reduction of nicotinamide adenine dinucleotide (NAD + ⇌ NADH). Interference is due to the similarity in absorbance peaks of NADH (340 nm) and metronidazole (322 nm) at pH 7.