Drug information of Telithromycin


Drug group:

Telithromycin, a semi-synthetic erythromycin derivative, belongs to a new chemical class of antibiotics called ketolides. Ketolides have been recently added to the macrolide-lincosamide-streptogramin class of antibiotics. Similar to the macrolide antibiotics, telithromycin prevents bacterial growth by interfering with bacterial protein synthesis.

Telithromycin binds to the 50S subunit of the 70S bacterial ribosome and blocks further peptide elongation. Binding occurs simultaneously at to two domains of 23S RNA of the 50S ribosomal subunit, domain II and V, where older macrolides bind only to one. It is used to treat mild to moderate respiratory infections.

Mechanism of effect

Inhibits bacterial protein synthesis by binding to two sites on the 50S ribosomal subunit. Telithromycin has also been demonstrated to alter secretion of IL-1alpha and TNF-alpha; the clinical significance of this immunomodulatory effect has not been evaluated.


Telithromycin is a ketolide antibiotic which has an antimicrobial spectrum similar or slightly broader than that of penicillin. It is often used as an alternative in patients who have an allergy to penicillins. For respiratory tract infections, it has better coverage of atypical organisms, including mycoplasma.

Telithromycin prevents bacterial growth by binding to bacterial 50S ribosomal subunits and interfering with bacterial peptide translocation and elongation.


  • Absorption: Rapid
  • Distribution: 2.9 L/kg
  • Protein binding: 60% to 70%; primarily to albumin
  • Metabolism: Hepatic, via CYP3A4 (50%) and non-CYP-mediated pathways
  • Bioavailability: 57%
  • Half-life elimination: 10 hours
  • Excretion: Urine (13% unchanged drug, remainder as metabolites); feces (7% unchanged drug)





Indicated for treatment of community-acquired pneumonia due to Streptococcus pneumoniae, (including multi-drug resistant isolates), Haemophilus influenzae, Moraxella catarrhalis, Chlamydophila pneumoniae, or Mycoplasma pneumoniae

800 mg PO qDay for 7-10 days 

Renal impairment (CrCl <30 mL/min): 600 mg PO qDay

Renal impairment (CrCl <30 mL/min) and hepatic impairment: 400 mg PO qDay


Concerns related to adverse effects:

Altered cardiac conduction: May prolong QTc interval, leading to a risk of ventricular arrhythmias, including torsades de pointes.

Hepatic effects: Acute hepatic failure and severe liver injury (some fatal), in some cases after only a few doses; if signs/symptoms of hepatitis or liver damage occur, discontinue therapy and initiate liver function testing. If clinical hepatitis or transaminase evaluations combined with other systemic symptoms occur, permanently discontinue.

Superinfection: Prolonged use may result in fungal or bacterial superinfection, including C. difficile-associated diarrhea (CDAD) and pseudomembranous colitis; CDAD has been observed >2 months postantibiotic treatment.

Visual disturbances: May cause visual disturbances (eg, changes in accommodation ability, diplopia, blurred vision); most cases are mild to moderate, but severe cases have been reported. Caution patients that these events may interfere with ability to operate machinery or drive, and to use caution until effects are known.

Disease-related concerns:

Myasthenia gravis: Life-threatening (including fatal) respiratory failure has occurred in patients with myasthenia gravis; use in these patients is contraindicated. Exacerbations of myasthenia gravis may occur within hours of the first dose.

Renal impairment: Use with caution in patients with renal impairment; severe impairment (CrCl <30 mL/minute) requires dosage adjustment.

Points of recommendation

It is common to have diarrhea when taking telithromycin. Rarely, a very bad form of diarrhea called Clostridium difficile (C diff)–associated diarrhea (CDAD) may occur. Sometimes, this has led to a deadly bowel problem (colitis). Patients should not try to treat loose stools without first checking with doctor.

May take with or without food

Pregnancy level


Ask a Pharmacist

User's questions
    No comments yet.