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Tyzeka Side Effects

Generic Name: telbivudine

Note: This document contains side effect information about telbivudine. Some of the dosage forms listed on this page may not apply to the brand name Tyzeka.

For the Consumer

Applies to telbivudine: oral solution, oral tablet

Along with its needed effects, telbivudine (the active ingredient contained in Tyzeka) 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 telbivudine:

More common
  • Chills
  • cough
  • diarrhea
  • fever
  • general feeling of discomfort or illness
  • headache
  • joint pain
  • loss of appetite
  • muscle aches and pains
  • nausea
  • runny nose
  • shivering
  • sore throat
  • stomach pain
  • sweating
  • trouble with sleeping
  • unusual tiredness or weakness
  • vomiting
Less common
  • Back pain
  • chest pain
  • difficulty with moving
  • muscle cramping
  • muscle stiffness
  • muscle tenderness, wasting, or weakness
  • pain
  • pain in the extremity
  • swollen joints
  • Burning feeling in the chest or stomach
  • indigestion
  • loose stools
  • stomach upset
  • tenderness in the stomach area
Incidence not known
  • Burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • dark-colored urine
  • decreased appetite
  • fast, shallow breathing
  • muscle pain or spasms
  • shortness of breath
  • sleepiness

Some side effects of telbivudine 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
  • Body aches or pain
  • difficulty with breathing
  • ear congestion
  • loss of voice
  • nasal congestion
  • sneezing
  • stuffy nose
Less common
  • Acid or sour stomach
  • belching
  • dizziness
  • heartburn
  • rash
  • sleeplessness
  • stomach discomfort
  • unable to sleep

For Healthcare Professionals

Applies to telbivudine: oral solution, oral tablet


In general, this drug was well tolerated in clinical studies, with most side effects described as mild or moderate. The most common side effects included grade 3 or 4 creatine phosphokinase elevations, fatigue, headache, and nausea.[Ref]


CPK elevations greater than 7 times the upper limit of normal (7 x ULN) was reported in 13% of patients.

In clinical trials, increased CPK occurred more often during treatment with this drug. By 104 weeks of therapy, 79% of patients using this drug (compared to 47% of patients using lamivudine) reported grade 1 to 4 CPK elevations; 13% of patients using this drug (compared to 4% of patients using lamivudine) reported grade 3 or 4 CPK elevations. Most patients with CPK elevations did not exhibit symptoms, but the average recovery time was longer with this drug than with lamivudine. Of the patients with grade 1 to 4 CPK elevations using this drug, 10% had a musculoskeletal side effect (compared to 5% of patients using lamivudine); these side effects included back pain, chest wall pain, noncardiac chest pain, chest discomfort, flank pain, muscle cramp, muscular weakness, musculoskeletal pain, musculoskeletal chest pain, musculoskeletal discomfort, musculoskeletal stiffness, myalgia, myofascial pain syndrome, myopathy, myositis, neck pain, and pain in extremity. By 208 weeks of therapy, 16% of patients using this drug reported grade 3 or 4 CPK elevations, most of which were asymptomatic (74% of patients had no muscle-related side effect), transient (98% lasted 1 or 2 visits), and resolved spontaneously or returned to baseline levels (93%).

Muscle-related symptoms (2%) included back pain, fibromyalgia, muscle cramp, musculoskeletal chest pain, myalgia, myopathy (including myositis), pain, pain in extremity, and tenderness.

Myopathy/myositis (presenting with muscular weakness) was diagnosed in less than 1% of patients. Cases of myopathy/myositis have been reported several weeks to months after this drug was started.[Ref]

Very common (10% or more): Increased blood creatine phosphokinase (CPK)
Common (1% to 10%): Arthralgia, back pain, myalgia, muscle-related symptoms
Uncommon (0.1% to 1%): Myopathy, myositis, muscular weakness, pain in the extremities, muscle spasm, neck pain, flank pain
Frequency not reported: Fibromyalgia, muscle strain, chest wall pain, noncardiac chest pain, chest discomfort, muscle cramp, musculoskeletal chest pain, musculoskeletal pain, musculoskeletal discomfort, musculoskeletal stiffness, myofascial pain syndrome, tenderness
Postmarketing reports: Rhabdomyolysis[Ref]


Very common (10% or more): Fatigue (up to 13%)
Common (1% to 10%): Malaise, pyrexia
Frequency not reported: Pain, influenza, influenza-like symptoms, postprocedural pain[Ref]

Nervous system

Common (1% to 10%): Headache, dizziness
Uncommon (0.1% to 1%): Peripheral neuropathy, dysgeusia, hypoesthesia, paresthesia, sciatica
Frequency not reported: Migraine, sinus headache, tension headache, vertigo[Ref]

Headache included headache, migraine, sinus headache, and tension headache.

Paresthesia and hypoesthesia have also been reported during postmarketing experience.[Ref]


Common (1% to 10%): Elevated ALT, elevated AST, acute hepatitis flare, hepatitis B exacerbation, ALT flares
Uncommon (0.1% to 1%): Elevated total bilirubin
Frequency not reported: Hypercholesterolemia, posttreatment exacerbations of hepatitis

Nucleoside analogs:
-Frequency not reported: Severe hepatomegaly with steatosis[Ref]

Elevated ALT (greater than 10 x ULN and 2 times baseline), elevated ALT (greater than 3 times baseline), elevated AST (greater than 3 times baseline), and elevated total bilirubin (greater than 5 x ULN) were reported in up to 6%, 7%, 6%, and less than 1% of patients, respectively.

The incidence of ALT flares (ALT greater than 10 x ULN and greater than 2 times baseline) was similar (3%) with this drug and lamivudine in the first 6 months. After week 24, reports of ALT flares decreased to 2% with this drug versus 5% with lamivudine.

In patients who stopped therapy early (for reasons excluding efficacy) or decided not to continue this drug in another trial, 6% reported exacerbation of hepatitis (ALT elevation greater than 10 x ULN and greater than 2 times baseline) during the 4 months posttherapy.

Severe acute exacerbations of hepatitis have been reported in patients who have discontinued this drug. Although most cases appeared self-limited or resolved by restarting therapy, severe hepatitis exacerbations (including fatalities) have been reported.

Lactic acidosis and severe hepatomegaly with steatosis (including fatalities) have been reported with the use of nucleoside analogs alone or in combination with antiretrovirals.[Ref]


Increased lipase (greater than 2.5 x ULN) and increased amylase (greater than 3 x ULN) were reported in 2% and less than 1% of patients, respectively.

Diarrhea/loose stools included diarrhea, loose stools, and frequent bowel movements. Abdominal pain included abdominal discomfort, abdominal pain, lower abdominal pain, upper abdominal pain, and gastrointestinal pain.[Ref]

Common (1% to 10%): Diarrhea/loose stools, increased blood lipase, nausea, abdominal pain, increased blood amylase, upper abdominal pain, abdominal distension, dyspepsia
Frequency not reported: Gastritis, sore throat, dry mouth, decreased appetite, abdominal discomfort, lower abdominal pain, gastrointestinal pain, frequent bowel movements[Ref]


Cough included cough and productive cough.[Ref]

Common (1% to 10%): Cough, pharyngolaryngeal pain
Frequency not reported: Upper respiratory tract infection, pharyngitis/nasopharyngitis[Ref]


Common (1% to 10%): Rash, pruritus
Frequency not reported: Acne[Ref]


Neutropenia (absolute neutrophil count up to 749/mm3) and thrombocytopenia (platelets up to 49,999/mm3) were reported in 2% and less than 1% of patients, respectively.[Ref]

Common (1% to 10%): Neutropenia
Uncommon (0.1% to 1%): Thrombocytopenia[Ref]


Common (1% to 10%): Insomnia


Lactic acidosis and severe hepatomegaly with steatosis (including fatalities) have been reported with the use of nucleoside analogs alone or in combination with antiretrovirals.[Ref]

Postmarketing reports: Lactic acidosis

Nucleoside analogs:
-Frequency not reported: Lactic acidosis[Ref]


Frequency not reported: Hematuria, irregular menstruation, polyuria[Ref]

At least 1 patient receiving a diuretic for ascites reported polyuria.[Ref]


1. "Product Information. Tyzeka (telbivudine)." IDEC Pharmaceuticals Corporation, San Diego, CA.

2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

3. Cerner Multum, Inc. "Australian Product Information." O 0

4. Matthews SJ "Telbivudine for the management of chronic hepatitis B virus infection." Clin Ther 29 (2007): 2635-53

5. Jones R, Nelson M "Novel anti-hepatitis B agents: A focus on telbivudine." Int J Clin Pract 60 (2006): 1295-9

6. "Telbivudine (Tyzeka) for chronic Hepatitis B." Med Lett Drugs Ther 49 (2007): 11-2

7. Keam SJ "Telbivudine." Drugs 67 (2007): 1917-29

8. Yuen MF, Lai CL "Telbivudine: an upcoming agent for chronic hepatitis B." Expert Rev Anti Infect Ther 3 (2005): 489-94

9. Hu P, Jiang J, Wang H, et al. "Single-dose and multiple-dose pharmacokinetics and safety of telbivudine after oral administration in healthy Chinese subjects." J Clin Pharmacol 46 (2006): 999-1007

10. Lai CL, Lim SG, Brown NA, et al. "A dose-finding study of once-daily oral telbivudine in HBeAg-positive patients with chronic hepatitis B virus infection." Hepatology 40 (2004): 719-26

11. Zhou XJ, Swan S, Smith WB, et al. "Pharmacokinetics of telbivudine in subjects with various degrees of renal impairment." Antimicrob Agents Chemother 51 (2007): 4231-5

12. Zhou XJ, Marbury TC, Alcorn HW, et al. "Pharmacokinetics of telbivudine in subjects with various degrees of hepatic impairment." Antimicrob Agents Chemother 50 (2006): 1721-6

Some side effects of Tyzeka may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.