Skip to main content

Telithromycin Side Effects

Medically reviewed by Last updated on May 14, 2023.

Applies to telithromycin: oral tablet.


Oral route (Tablet)

Fatal and life-threatening respiratory failure has been reported in patients with myasthenia gravis treated with telithromycin.

Serious side effects of Telithromycin

Along with its needed effects, telithromycin may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking telithromycin:


Incidence not known

Other side effects of Telithromycin

Some side effects of telithromycin may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

Less common

For Healthcare Professionals

Applies to telithromycin: oral tablet.


Severe liver injury and acute liver failure (in some cases fatal) have been reported. Such hepatic reactions were observed during or immediately after therapy and included fulminant hepatitis and hepatic necrosis leading to liver transplant. In some cases, liver injury progressed rapidly and occurred after a few doses of this drug were administered. Less severe liver dysfunction (associated with reversible hepatitis, elevated liver enzymes, and sometimes jaundice) has been reported.

Drug-related hepatotoxicity was reported in a 46-year-old man receiving treatment for an ear and sinus infection. The patient presented with a 4-day history of malaise, dark urine, jaundice, mild pruritus, and anorexia. The patient denied toxin exposure, IV drug abuse, or hepatic injury. ALT 948 units/L, AST 200 units/L, total bilirubin 65 mmol/L, and alkaline phosphatase 291 units/L were observed. These values warranted withdrawal of this drug and within 2 weeks the ALT decreased to 450 units/L and his jaundice resolved. After 8 weeks, the patient's liver tests had normalized.[Ref]

Common (1% to 10%): Increased liver enzymes (AST, ALT, alkaline phosphatase, GGT)

Uncommon (0.1% to 1%): Hepatitis (with or without jaundice)

Rare (0.01% to 0.1%): Cholestatic jaundice

Frequency not reported: Abnormal liver function tests, increased transaminases (ALT, AST), elevated blood bilirubin, increased ALT (at least 3 times the upper limit of normal), hepatocellular and/or cholestatic hepatitis (with or without jaundice), severe liver toxicity, hepatotoxicity (including acute liver failure, severe liver injury)

Postmarketing reports: Hepatic dysfunction, fulminant hepatitis, hepatic necrosis, hepatic failure, severe hepatitis[Ref]


Very common (10% or more): Diarrhea (10.8%)

Common (1% to 10%): Nausea, vomiting, gastrointestinal pain, flatulence

Uncommon (0.1% to 1%): Constipation, oral candidiasis, stomatitis

Very rare (less than 0.01%): Pseudomembranous colitis

Frequency not reported: Abdominal distension, dry mouth, dyspepsia, gastrointestinal upset, gastroenteritis, gastritis, glossitis, Clostridium difficile-associated diarrhea, loose stools, watery stools

Postmarketing reports: Pancreatitis[Ref]

Pseudomembranous colitis has also been reported during postmarketing experience.[Ref]

Nervous system

Exacerbations of myasthenia gravis (including fatal and life-threatening acute respiratory failure) have been reported. Rapid onset was observed in some cases, occurring within a few hours after the first dose.[Ref]

Common (1% to 10%): Headache, dizziness (excluding vertigo), taste disturbance/dysgeusia

Uncommon (0.1% to 1%): Somnolence, vertigo

Rare (0.01% to 0.1%): Paresthesia, transient loss of consciousness

Very rare (less than 0.01%): Parosmia

Postmarketing reports: Loss of consciousness (in some cases associated with vagal syndrome), exacerbation of myasthenia gravis, tremors, convulsions, taste/smell perversion, ageusia, anosmia, hearing loss[Ref]


Frequency not reported: Acute respiratory failure, rhinitis, upper respiratory infection

Postmarketing reports: Dyspnea[Ref]

Fatal and life-threatening acute respiratory failure has been reported in patients with myasthenia gravis.[Ref]


Common (1% to 10%): Vaginal candidiasis

Frequency not reported: Vaginitis, fungal vaginosis

Postmarketing reports: Chromaturia[Ref]


Uncommon (0.1% to 1%): Flush/flushing, palpitations

Rare (0.01% to 0.1%): Atrial arrhythmia, hypotension, bradycardia

Frequency not reported: Increased QTc interval

Postmarketing reports: QT/QTc interval prolongation, ventricular arrhythmias (including ventricular tachycardia, torsades de pointes) with potential fatal outcome, ischemic cardiac events (in the context of hypersensitivity reactions)[Ref]

Ventricular arrhythmias (including ventricular tachycardia, torsades de pointes) have sometimes occurred within a few hours after the first dose.

Atrial arrhythmias and palpitation have also been reported during postmarketing experience.[Ref]


Visual disturbances (some severe) most often included blurred vision, difficulty focusing, or diplopia; some patients stopped therapy due to these effects. Most visual side effects were reported after the first or second dose, lasted several hours, and recurred with subsequent doses in some patients. Symptoms continued throughout the entire course of therapy in some patients and resolved spontaneously during therapy in others. Females and patients up to 40 years of age had a higher rate of these side effects (females up to 40 years: 2.1%; females older than 40 years: 1%; males up to 40 years: 1.2%; males older than 40 years: 0.27%).[Ref]

Uncommon (0.1% to 1%): Blurred vision

Rare (0.01% to 0.1%): Diplopia

Frequency not reported: Visual disturbances (including blurred vision, difficulty focusing, diplopia)[Ref]


Uncommon (0.1% to 1%): Rash, pruritus, urticaria

Rare (0.01% to 0.1%): Eczema

Very rare (less than 0.01%): Erythema multiforme

Frequency not reported: Increased sweating

Postmarketing reports: Angioneurotic edema[Ref]


Uncommon (0.1% to 1%): Eosinophilia

Frequency not reported: Increased platelet count, increased eosinophil count[Ref]


Uncommon (0.1% to 1%): Anorexia

Frequency not reported: Increased blood alkaline phosphatase[Ref]


Uncommon (0.1% to 1%): Insomnia, nervousness

Frequency not reported: Anxiety

Postmarketing reports: Confusion, hallucinations (mostly visual)


Very rare (less than 0.01%): Muscle cramps

Postmarketing reports: Arthralgia, myalgia[Ref]

Muscle cramps have also been reported during postmarketing experience.[Ref]


Postmarketing reports: Severe allergic reactions (including angioedema, anaphylaxis), anaphylactic reactions (including anaphylactic shock), hypersensitivity[Ref]


Frequency not reported: Abdominal pain, fatigue, upper abdominal pain

Postmarketing reports: Face edema


1. Product Information. Ketek (telithromycin). Aventis Pharmaceuticals. 2004.

2. Banks MD, Hanson JS, Rissmiller RW, Pope SD, Clay KD, Purdum PP 3rd. Brief Communication: Severe hepatotoxicity of telithromycin: three case reports and literature review. 2006.

3. Clay KD, Hanson JS, Pope SD, Rissmiller RW, Purdum PP 3rd, Banks PM. Brief communication: severe hepatotoxicity of telithromycin: three case reports and literature review. Ann Intern Med. 2006;144:E1-E6.

4. Onur O, Guneysel O, Denizbasi A, Celikel C. Acute hepatitis attack after exposure to telithromycin. Clin Ther. 2007;29:1725-1729.

5. Owens RC Jr, Nolin TD. Antimicrobial-Associated QT Interval Prolongation: Pointes of Interest. Clin Infect Dis. 2006;43:1603-1611.

6. Nieman RB, Sharma K, Edelberg H, Caffe SE. Telithromycin and myasthenia gravis. Clin Infect Dis. 2003;37:1579.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.