Roxithromycin

Oral
Tonsillitis, Sinusitis, Skin and soft tissue infections, Nongonococcal urethritis, Acute bronchitis, Acute exacerbations of chronic bronchitis, Community-acquired pneumonia, Acute pharyngitis
Adult: Recommended dose: 150 mg bid or 300 mg once daily for 5-10 days. Duration of treatment may be longer depending on the indication and clinical response.
Child: 6-40 kg: 5-8 mg/kg daily given in 2 divided doses; ≥40 kg: 150 mg bid. Usual treatment duration: 5-10 days. Duration of treatment must not exceed 10 days.
Hepatic impairment: Severe: Contraindicated.

Should be taken on an empty stomach. Take at least 15 min before meals.

Hypersensitivity. Severe hepatic impairment. Concomitant use with vasoconstrictive ergot alkaloids.

Patient with risk factors for prolonged cardiac repolarisation, history of torsade de pointes, congenital or documented QT prolongation, electrolyte disturbances (particularly hypokalaemia and hypomagnesaemia); clinically significant bradycardia, cardiac arrhythmia, or other cardiac insufficiencies; myasthenia gravis. Patients currently receiving agents known to prolong QT interval (e.g. class IA or class III antiarrhythmic agents, astemizole, cisapride, pimozide). Renal and mild to moderate hepatic impairment. Children and elderly. Pregnancy and lactation. Patient Counselling This drug may cause dizziness and visual impairment such as blurred vision, if affected, do not drive or operate machinery. Monitoring Parameters Perform culture and susceptibility tests; consult local institutional recommendations before treatment initiation due to antibiotic resistance risks. Monitor LFTs and CBC with differential.

Significant: Bacterial or fungal superinfection (prolonged-use), aggravation of myasthenia gravis. Rarely, hepatocellular and/or cholestatic hepatitis (with or without jaundice). Blood and lymphatic system disorders: Eosinophilia, neutropenia, thrombocytopenia. Ear and labyrinth disorders: Tinnitus, vertigo, temporary deafness, hypoacusis. Eye disorders: Blurred vision, visual impairment. Gastrointestinal disorders: Nausea, vomiting, epigastric pain, diarrhoea, flatulence, taste disorders, pancreatitis. General disorders and administration site conditions: Malaise. Infections and infestations: Candidiasis. Immune system disorders: Angioedema. Investigations: Increased serum AST, ALT, and alkaline phosphatase levels. Metabolism and nutrition disorders: Anorexia. Nervous system disorders: Dizziness, headache, paraesthesia. Psychiatric disorders: Hallucinations, confusion. Respiratory, thoracic and mediastinal disorders: Smell disorders, bronchospasm. Skin and subcutaneous tissue disorders: Rash, pruritus.
Potentially Fatal: Severe skin reactions such as Stevens-Johnson syndrome, toxic epidermal necrolysis, and erythema multiforme; antibiotic-associated pseudomembranous colitis or Clostridium difficile-associated diarrhoea; QT prolongation, ventricular tachycardia, and torsades de pointes.

Increased risk of CV adverse effects, including QT prolongation, torsades de pointes, and other ventricular arrhythmias with class IA (e.g. quinidine, procainamide) and class III (e.g. amiodarone, dofetilide) antiarrhythmic agents, terfenadine, astemizole, cisapride, and pimozide. May increase the absorption of digoxin and other cardiac glycosides. Increased INR levels resulting in bleeding episodes with anticoagulants (e.g. warfarin). May increase the plasma concentrations of theophylline, disopyramide, and ciclosporin. May enhance and prolong the effect of midazolam. May increase the exposure to drugs metabolised by CYP3A (e.g. bromocriptine, rifabutin).
Potentially Fatal: May result in severe vasoconstriction (ergotism) and possible necrosis of extremities when given with vasoconstrictive ergot alkaloids (e.g. ergotamine, dihydroergotamine).

Decreased extent of absorption with food.

Roxithromycin is a macrolide that acts as bactericidal at high concentrations and bacteriostatic at low concentrations. It disrupts bacterial protein synthesis by binding to the 50S subunit of the 70S ribosome.
Absorption: Rapidly absorbed from the gastrointestinal tract. Food reduces the extent of absorption. Bioavailability: Approx 50%. Time to peak plasma concentration: Approx 1-2 hours.
Distribution: Widely distributed into tissues and body fluids; highly concentrated in polymorphonuclear leucocytes and macrophages (approx 30 times serum levels). Enters breastmilk (small amounts). Plasma protein binding: 92-96%, mainly to α₁-acid glycoprotein and albumin.
Metabolism: Undergoes limited metabolism in the liver into the major metabolite, descladinose roxithromycin.
Excretion: Mainly via faeces (approx 53% as unchanged drug and metabolites); lungs (13%); urine (approx 7%). Elimination half-life: Approx 12 hours (adults); 20 hours (children).

Oral: Store between 15-30°C. Protect from light and moisture.

Macrolides

J01FA06 - roxithromycin ; Belongs to the class of macrolides. Used in the systemic treatment of infections.