Roxithromycin

Roxithromycin is a macrolide antibiotic used for various bacterial infections. Among other things, it is used for respiratory tract infections, skin and soft tissue infections, and infections of the urogenital tract.

For gynecological infections, roxithromycin can be used as an alternative, especially in mixed infections with atypical pathogens (chlamydia, mycoplasma) or in cases of intolerance to penicillins and metronidazole.

Mechanism of action:

• Inhibits bacterial protein synthesis
• Binds to the 50S subunit of the ribosome
• Bacteriostatic (partly bactericidal at high concentrations)

Spectrum of activity:

• Gram-positive bacteria (streptococci, staphylococci)
• Atypical pathogens: Chlamydia trachomatis, Mycoplasma, Ureaplasma
• Some gram-negative pathogens

Pharmacokinetics:

• Good tissue penetration
• Long half-life (approx. 12 hours)
• Taken once or twice daily

Roxithromycin is suitable for:

• Infections with atypical pathogens (chlamydia, mycoplasma)
• Patients with a penicillin allergy (as an alternative)
• Respiratory tract infections, skin and soft tissue infections
• Urethritis (non-gonococcal)

Not suitable:

• Severe hepatic insufficiency
• Concomitant use of ergotamine
• Hypersensitivity to macrolides

Standard dosage:

• 150 mg twice daily for 7–14 days
• Or 300 mg once daily

Available strengths:

• 150 mg, 300 mg tablets

Dose adjustment:

• In severe hepatic insufficiency: half the dose or an alternative medication

How to take:

• Take before meals (15 minutes before eating)
• Taking it on an empty stomach improves absorption
• Swallow the tablet whole with water

Important notes:

• Complete the full course of treatment
• Do not stop early
• Contact a doctor if you develop a skin rash or liver problems

Roxithromycin must not be taken in cases of:

• Hypersensitivity to macrolides
• Concomitant use of ergotamine/dihydroergotamine
• Concomitant use of astemizole, cisapride, pimozide

Use with caution in:

• Liver disease: Use is not recommended. If it is nevertheless necessary, liver values are monitored. In severe hepatic insufficiency, the daily dose is halved.
• QT prolongation
• Myasthenia gravis

Common (1–10%):

• Nausea, abdominal pain
• Diarrhea
• Headache
• Dizziness

Uncommon (0.1–1%):

• Skin rash
• Elevated liver enzymes
• Taste disturbances
• Candidiasis

Rare:

• Hepatitis
• QT prolongation
• Severe allergic reactions

General: Roxithromycin is generally well tolerated, better than erythromycin with regard to gastrointestinal complaints.

Do not take together with:

• Ergot alkaloids such as ergotamine or dihydroergotamine (risk of increased vasoconstriction)
• Medicines with a narrow therapeutic range that are broken down via CYP3A4, in particular astemizole, cisapride, pimozide and terfenadine (risk of heart rhythm disorders and QT prolongation)

Particular caution with medicines that prolong the QT interval:

• Antiarrhythmics such as quinidine, procainamide, disopyramide, amiodarone or dofetilide
• Citalopram, tricyclic antidepressants, methadone
• Neuroleptics such as phenothiazines
• Fluoroquinolones such as moxifloxacin
• Antifungals such as fluconazole or pentamidine
• Antiviral medicines such as telaprevir

Monitoring or caution needed with:

• Vitamin K antagonists such as warfarin: In isolated cases, the anticoagulant effect can be increased. Monitoring of clotting values (Quick value, INR) is advisable.
• Digoxin and other cardiac glycosides: Very rarely, the toxicity of the cardiac glycosides can be increased. ECG monitoring and, if possible, monitoring of blood levels.
• Disopyramide: ECG monitoring and, if possible, monitoring of blood levels.
• Statins: Possible risk of muscle-related side effects such as rhabdomyolysis. Watch out for muscle complaints.
• Theophylline: The theophylline level can rise and should be monitored.
• Ciclosporin: The ciclosporin level can rise. Levels and kidney function should be monitored.
• Midazolam, bromocriptine, rifabutin: The blood levels of these active substances can rise.

Contraceptive pill:

• In rare cases, especially with vomiting or diarrhea, the effect of the pill may be unreliable. It is advisable to use an additional non-hormonal method of contraception during treatment.