clarithromycin

Contraindications
Hypersensitivity to clarithromycin, erythromycin, or any macrolide antibiotic; use with ergot derivatives, pimozide, cisapride; combination with ranitidine bismuth citrate should not be used in patients with history of acute porphyria or Clcr<25 mL/minute


Warnings/Precautions
Dosage adjustment required with severe renal impairment, decreased dosage or prolonged dosing interval may be appropriate; antibiotic-associated colitis has been reported with use of clarithromycin. Macrolides (including clarithromycin) have been associated with rare QT prolongation and ventricular arrhythmias, including torsade de pointes. The extended release formulation consists of drug within a nondeformable matrix; following drug release/absorption, the matrix/shell is expelled in the stool. The use of nondeformable products in patients with known stricture/narrowing of the GI tract has been associated with symptoms of obstruction. Safety and efficacy in children <6 months of age have not been established.


Adverse Reactions

1% to 10%:

Central nervous system: Headache (adults and children 2%)

Dermatologic: Rash (children 3%)

Gastrointestinal: Diarrhea (adults 6%, children 6%); vomiting (children 6%); nausea (adults 3%); abnormal taste (adults 7%); heartburn (adults 2%); abdominal pain (adults 2%, children 3%)

Hepatic: Prothrombin time increased (1%)

Renal: BUN increased (4%)

<1%, postmarketing, and/or case reports (limited to important or life-threatening); Clostridium difficile colitis, alkaline phosphatase increased, anaphylaxis, anorexia, anxiety, AST increased, bilirubin increased, dizziness, dyspnea, glossitis, hallucinations, hearing loss (reversible), hepatic failure, hepatitis, hypoglycemia, jaundice, leukopenia, manic behavior, neuromuscular blockade (case reports), neutropenia, pancreatitis, psychosis, QT prolongation, seizure, serum creatinine increased, Stevens-Johnson syndrome, thrombocytopenia, tongue discoloration, tooth discoloration, torsade de pointes, toxic epidermal necrolysis, tremor, ventricular tachycardia, vertigo, vomiting

Overdosage/Toxicology
Symptoms of overdose include nausea, vomiting, diarrhea, prostration, reversible pancreatitis, hearing loss with or without tinnitus, or vertigo. Treatment includes symptomatic and supportive care.