Side Effects of Combivir (lamivudine and zidovudine)

Combivir is a combination of antiviral drugs used to treat HIV infection.

Combivir decreases the amount of HIV in the body to improve the immune system and reduce HIV complications and improve quality of life. It is not a cure for HIV infection.

Common side effects of Combivir include:

Serious side effects of Combivir include:

• decreased blood cells
• muscle pain
• muscle breakdown (rhabdomyolysis)
• pancreatitis
• liver enlargement
• immune reconstitution syndrome
• exacerbation of hepatitis B
• fatty liver
• hypersensitivity reactions
• metabolic disturbance (lactic acidosis)

Drug interactions of Combivir include fluconazole, probenecid, trimethoprim, and valproic acid, which increase the concentration of zidovudine in the blood and can lead to increased side effects.

• Combivir should not be combined with zalcitabine.
• Combining zidovudine with ganciclovir, interferon alfa, ribavirin, or other drugs that suppress bone marrow production of blood cells can increase the effect of zidovudine on blood cell production.

Use of Combivir during pregnancy has not been adequately evaluated but reduces the transmission of HIV to the baby in infected women.

Use of Combivir by nursing mothers has not been studied. The drugs are excreted in breast milk, so it is not recommended for HIV infected mothers to breastfeed.

Important Side Effects of Combivir (lamivudine and zidovudine)

The most serious side effects of Combivir are:

• decrease in blood cells
• muscle pain (myopathy)
• muscle breakdown (rhabdomyolysis)
• pancreatitis
• liver enlargement
• immune reconstitution syndrome
• exacerbation of hepatitis B
• fatty liver
• hypersensitivity reactions
• metabolic disturbance (lactic acidosis)

Other side effects include accumulation or redistribution of fat.

Combivir (lamivudine and zidovudine) side effects for healthcare professionals

The following adverse reactions are discussed in other sections of the labeling:

• Hematologic toxicity, including neutropenia and anemia
• Symptomatic myopathy
• Lactic acidosis and severe hepatomegaly with steatosis
• Exacerbations of hepatitis B
• Hepatic decompensation in patients co-infected with HIV-1 and hepatitis C
• Exacerbation of anemia in HIV-1/HCV co-infected patients receiving ribavirin and zidovudine
• Pancreatitis
• Immune reconstitution syndrome
• Lipoatrophy

Clinical Trials Experience

Because clinical trials are conducted under varying conditions, adverse reaction rates observed in the trials of one drug cannot be directly compared with rates in the trials of another drug.

Lamivudine Plus Zidovudine Administered Separately

In 4 randomized, controlled trials of Epivir plus Retrovir, the following selected adverse reactions and laboratory abnormalities were observed:

Selected Clinical Adverse Reactions (Greater than or Equal to 5% Frequency) in 4 Controlled Clinical Trials with Epivir plus Retrovir

Pancreatitis was observed in 9 of the 2,613 adult subjects (0.3%) who received Epivir in controlled clinical trials.

Selected laboratory abnormalities observed during therapy are listed in Table 2.

Frequencies of Selected Laboratory Abnormalities among Adults in 4 Controlled Clinical Trials of Epivir plus Retrovir a

Postmarketing Experience

The following adverse reactions have been identified during postmarketing use:

Body As A Whole

• Redistribution/accumulation of body fat.

Cardiovascular

Endocrine And Metabolic

Gastrointestinal

• Oral mucosal pigmentation, stomatitis.

General

• Vasculitis, weakness.

Hemic And Lymphatic

• Anemia, lymphadenopathy, splenomegaly.

Hepatic And Pancreatic

• Lactic acidosis and hepatic steatosis, pancreatitis, posttreatment exacerbations of hepatitis B.

Hypersensitivity

• Sensitization reactions, urticaria.

Musculoskeletal

• Muscle weakness, CPK elevation, rhabdomyolysis.

Nervous

• Paresthesia, peripheral neuropathy, seizures.

Respiratory

• Abnormal breath sounds/wheezing.

Skin

• Alopecia, erythema multiforme, Stevens-Johnson syndrome.