Lamivudine/Zidovudine (Combivir) - Uses, Side Effects, and More

What are the most common side effects of lamivudine/zidovudine?

The most common side effects of lamivudine/zidovudine are listed below. Tell your health care provider if you have any of these side effects that bother you.

• Headache
• Nausea and vomiting
• General feeling of being unwell, tired, or not having your usual energy
• Weight loss or decreased appetite
• Diarrhea
• Cough
• Fever or chills
• Nerve problems, such as pain, burning, tingling, numbness, or weakness in your arms, hands, legs, or feet
• Trouble sleeping
• Dizziness
• Nasal symptoms
• Muscle or joint pain

There may be other side effects of lamivudine/zidovudine that are not listed here. Contact your health care provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088 (800-332-1088). In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of lamivudine/zidovudine?

While less common, the most serious side effects of lamivudine/zidovudine are described below, along with what to do if they happen.

Severe Allergic Reactions. Lamivudine/zidovudine may cause allergic reactions, which can be serious. Stop taking lamivudine/zidovudine and get help right away if you have any of the following symptoms of a serious allergic reaction.

• Breathing problems or wheezing
• Racing heart
• Fever or general ill feeling
• Swollen lymph nodes
• Swelling of the face, lips, mouth, tongue, or throat
• Trouble swallowing or throat tightness
• Itching or skin rash
• Bumps on the skin called hives that can be red, pink, white, or brown depending on your skin tone
• Nausea or vomiting
• Dizziness, feeling lightheaded, or fainting
• Stomach cramps
• Joint pain

Blood Disorders. Lamivudine/zidovudine can cause blood disorders, such as aplastic anemia, hemolytic anemia, and low white blood cell levels. Get help right away if you have any of the following symptoms of blood disorders.

• Fever
• Shortness of breath
• Pale or yellowish skin
• Easy bruising or bleeding
• Frequent infection
• Unusual weakness or tiredness
• Dizziness, lightheadedness, or feeling like you are about to pass out
• Headache
• Fast or abnormal heartbeat

Low Neutrophil Levels (Neutropenia). Lamivudine/zidovudine may cause low levels of a type of white blood cell (called neutrophils), which is known as neutropenia. Neutrophils help prevent infection. Having a low level of neutrophils may increase your risk of infection. Tell your health care provider right away if you have any of the following symptoms of low neutrophil levels.

• Fever, chills, or sweats
• Tiredness
• Sore throat, cough, or shortness of breath
• Mouth or throat sores
• Swollen lymph nodes

Muscle Problems. Lamivudine/zidovudine can cause muscle problems, including muscle pain, weakness, and tenderness called myopathy. In some people, the muscle may break down (rhabdomyolysis), which can be serious and rarely lead to kidney damage and death. Get help right away if you have any of the following symptoms of myopathy or rhabdomyolysis.

• Unexplained muscle pain, weakness, or tenderness
• Low energy levels or feeling easily tired, especially with activity
• Dark-colored urine (pee)
• Fever
• Muscle cramps
• Stomach pain
• Nausea or vomiting

Lactic Acidosis. Lamivudine/zidovudine may cause lactic acidosis (a buildup of lactic acid in your blood), which can be serious. Stop taking lamivudine/zidovudine and get help right away if you have any of the following symptoms of lactic acidosis.

• General ill feeling
• Muscle pain
• Trouble breathing
• Drowsiness
• Stomach pain, nausea, or vomiting

Liver Damage. Liver damage, also called hepatotoxicity, can happen when taking lamivudine/zidovudine. Call your health care provider right away if you have any of the following symptoms of liver damage.

• Nausea or vomiting
• Stomach or belly pain
• Fever
• Weakness or unusual tiredness
• Itching
• Loss of appetite
• Light-colored poop
• Dark-colored urine (pee)
• Your skin or the whites of your eyes turning yellowish in color (also called jaundice)

Inflammation of the Pancreas (Pancreatitis). Lamivudine/zidovudine may cause inflammation of the pancreas, which is called pancreatitis. Stop taking lamivudine/zidovudine and call your health care provider right away if you have symptoms of pancreatitis, including vomiting or severe pain in the upper part of your belly that travels to your back.

Immune System Changes. When you start lamivudine/zidovudine, your immune system might get stronger and start fighting infections that have been hiding inside your body for a long time. The type of symptoms you may have will depend on the infection. Tell your health care provider right away if you notice any of the following new symptoms of infection.

• Fever, sweats, chills, or muscle aches
• Swollen lymph nodes
• Vision problems
• Confusion, problems talking, or headache
• Skin problems, such as a painful rash or warts
• Cough or coughing up blood
• Weakness or coordination problems

Fat Redistribution. Some people taking lamivudine/zidovudine have changes in how their body stores fat. You may lose fat in your arms, legs, face, or butt. You may get more fat around the belly, breasts, or upper back (buffalo hump). Tell your health care provider right away if you have any of these symptoms.

Severe Skin Reactions. Lamivudine/zidovudine may cause severe skin reactions, such as Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN), that can lead to death if not treated. If you get a rash, call your health care provider right away. Get emergency help if you have any of the following symptoms of SJS or TEN.

• Painful red or purple skin that looks burned and peels off
• Flat red rash or blisters on your skin, mouth, nose, and genitals
• Red, painful, watery eyes