Common uses

Retrovir is prescribed for adults infected with human immunodeficiency virus (HIV). HIV causes the immune system to break down so that it can no longer respond effectively to infection, leading to the fatal disease known as acquired immune deficiency syndrome (AIDS). Retrovir slows down the progress of HIV. Combining Retrovir with other drugs such as Epivir and Crixivan can help slow the progression.
Retrovir is also prescribed for HIV-infected children over 3 months of age who have symptoms of HIV or who have no symptoms but, through testing, have shown evidence of impaired immunity.
Retrovir taken during pregnancy often prevents transmission of HIV from mother to child.
Signs and symptoms of HIV disease are significant weight loss, fever, diarrhea, infections, and problems with the nervous system.

Before using

Before taking this medication, tell your doctor if you have kidney disease, liver disease, a history of pancreatitis, or decreased activity of your bone marrow (low red blood cells [anemia] or low white blood cells). You may not be able to take Retrovir, or you may require lower doses or special monitoring during treatment, if you have any of these conditions.

Directions

Take Retrovir exactly as prescribed by your doctor. Do not share Retrovir with anyone and do not exceed your recommended dosage. Take it at even intervals every 4 hours around the clock (children every 6 hours).
If you are pregnant, take the drug 5 times a day.
-If you miss a dose...
Take it as soon as you remember. If it is almost time for your next dose, skip the one you missed and go back to your regular schedule. Do not take 2 doses at once.
-Storage instructions...
Tablets, capsules, and syrup should be stored at room temperature; keep capsules away from moisture.
Cautions

A set of rare but serious side effects of nucleoside analog anti-HIV drugs is called lactic acidosis and severe hepatomegaly with steatosis (an enlarged fatty liver). Women, especially those who are oveweight, are particularly at risk. This set of side effects is probably the result of mitochondrial toxicity. Mitochondria are cell's power organs that supply the energy needed for normal cell growth. Anti-HIV nucleoside analogs impair the function of mitochondria. This can lead to increased acid levels in the blood, and an enlarged fatty liver. The symptoms are severe nausea, shortness of breath and vomiting that does not get better. If you are taking anti-HIV drugs and experience these symptoms, tell your provider immediately.

Possible side effects

Bone marrow problems, such as decreased production of red blood cells and/or white blood cells, can occur in people talking Retrovir. Contact your doctor immediately if you develop unusual fatigue, pale skin, sore throat, fever, or chills, which may be signs of bone marrow problems. These problems are more likely to occur if you combine Retrovir with other drugs that cause these same side effects. Examples of other drugs that can cause bone marrow problems include ganciclovir (Cytovene), SMX-TMP (Bactrim; Septra), and various chemotherapy drugs used to treat cancer.

A rare but potentially serious side effect of Retrovir is myopathy (damage to the muscles, including the heart). People who use Retrovir for a long period of time, meaning several years, are at the greatest risk for myopathy. General symptoms of myopathy include weakness of limbs, usually proximal (located close to the center of the body).

Lactic acidosis, which can be fatal, and severe liver problems (fatty liver) have been reported in people taking nucleoside reverse transcriptase inhibitors (NRTIs). Contact your doctor immediately if you experience nausea, vomiting, or unusual or unexpected stomach discomfort; weakness and tiredness; shortness of breath; weakness in the arms and legs; yellowing of the skin or eyes; or pain in the upper stomach area. These problems are more likely to occur in HIV-positive people taking Zerit (d4T), or Zerit in combination with Videx/Videx EC (ddI). However, there have been some reports of these potentially serious side effects occurring in people taking Retrovir.

Feeling tired (fatigue), rash, trouble sleeping (insomnia), nausea, and headache can also be caused by Retrovir. Side effects are more likely to occur in people who have low T-cell counts at the time therapy with Retrovir is started.

Anti-HIV drug regimens containing NRTIs, including Retrovir, can cause increased fat levels (cholesterol and triglycerides) in the blood, abnormal body-shape changes (lipodystrophy; including increased fat around the abdomen, breasts, and back of the neck, as well as decreased fat in the face, arms, and legs), and diabetes. These side effects of anti-HIV drug therapy are reviewed in our lessons on Lipodystrophy, Facial Lipoatrophy, and Risks To Your Heart (Hyperlipidemia).

If you take too much

Any medication taken in excess can have serious consequences. If you suspect an overdose, seek emergency medical treatment immediately.
• Symptoms of Retrovir overdose may include:
Fatigue, headache, nausea, vomiting

Additional information

The long-term effects of treatment with zidovudine are unknown. However, treatment with Retrovir may lead to blood diseases, including granulocytopenia (a severe blood disorder characterized by a sharp decrease of certain types of white blood cells called granulocytes) and severe anemia requiring blood transfusions. This is especially true in women, individuals who are overweight, people who have been using Retrovir for a long time, people with more advanced HIV, and those who start treatment later in the course of their infection.
Drug interactions
Retrovir should not be combined with Zerit (d4T). They are "antagonistic," which means that they do not work well together and can cause additional side effects.

Some laboratory studies have suggested that Retrovir should not be combined with either Rebetol or Copegus, two brand-name versions of ribavirin. Ribavirin is an oral medication used to treat hepatitis C. In these studies, ribavirin appeared to affect the way Retrovir is broken down by the body into its active form. This can make Retrovir less effective against HIV. However, many doctors report that this hasn't been in a problem in their patients taking both drugs.

Retrovir can interact with some medications used to treat TB, MAC and other bacterial infections. Rifadin (rifampin) and Mycobutin (rifabutin) can lower levels of Retrovir in the bloodstream, which can cause the drug to be less effective against HIV. If you need to take Rifadin or Mycobutin, it might be necessary to switch your Retrovir for another nucleoside reverse transcriptase inhibitor (NRTI) that does not interact with these drugs.