Retrovir – Zidovudine uses, dose and side effects


100 mg and 250 mg zidovudine capsule

What Retrovir is and what it is used for

Retrovir is used to treat HIV infection ( human immunodeficiency virus ).

The active substance in Retrovir is zidovudine. Retrovir belongs to a group of antiretroviral medicines called nucleoside reverse transcriptase inhibitors (NRTIs).

Retrovir cannot cure HIV infection; it reduces the amount of virus in the body and keeps it at a low level. Retrovir also increases the number of CD4 cells in the blood. CD4 cells are a type of white blood cell that is important for the body to fight infection.

Retrovir is used in combination with other medicines (“combination therapy”) to treat HIV in adults and children. To keep your HIV infection under control and to prevent the disease from getting worse, you must continue to take all your medicines.

If you are pregnant, your doctor may want you to take Retrovir to prevent the transmission of HIV from you to your baby. After birth, your baby can receive Retrovir to prevent it from becoming infected with HIV.

HIV infection is spread through sexual contact with an infected person, or through contact with infected blood (eg by splitting injection needles).

What you need to know before you take Retrovir

Do not take Retrovir

  • if you are allergic ( hypersensitive ) to zidovudine or any of the other ingredients of Retrovir (mentioned in section 6).
  • if you have a very low white blood cell count ( neutropenia ) or a very low red blood cell count ( anemia ).

Retrovir for newborns

Retrovir should not be given to newborns with certain liver problems, including:

  • certain cases of hyperbilirubinemia (increased amount of the substance bilirubin in the blood which may cause the skin to turn yellow)
  • other problems that cause elevated levels of liver enzymes in the blood.

Take special care with Retrovir

Some people who use Retrovir or combination therapy for HIV are at greater risk for side effects. You need to be aware of the extra risks:

  • if you have ever had any liver disease (including hepatitis B or C)
  • if you are severely overweight (especially if you are a woman).
  • Tell your doctor if any of these apply to you. You may need extra checks, including blood tests, while you are taking this medicine. See section 4 for more information.

Pay attention to important symptoms

Some people who use medicines for HIV infection develop other conditions, which can be serious. You need to know the important characteristics and symptoms to notice while you are taking Retrovir.

Read the information in section 4 of this leaflet. If you have questions regarding this information or advice given there:

  • Talk to your doctor.

Other medicines and Retrovir

Tell your doctor or pharmacist if you are taking or have recently taken any other medicines, including medicines obtained without a prescription, herbal medicines, herbal medicines, or other natural products. Remember to tell your doctor or pharmacist if you start taking a new medicine while taking Retrovir.

Do not use these medicines with Retrovir:

  • stavudine is used to treat HIV infection
  • ribavirin or injection of ganciclovir to treat viral infections
  • rifampicin, which is an antibiotic.

Some medicines may make you more likely to get side effects or make them more difficult to get rid of.

These include:

  • sodium valproate is used to treat epilepsy
  • aciclovir, ganciclovir, or interferon, are used to treat viral infections
  • pyrimethamine is used to treat malaria and other parasitic infections
  • dapsone is used to prevent pneumonia and treat skin infections
  • fluconazole or flucytosine is used to treat fungal infections such as candida
  • pentamidine or atovaquone is used to treat parasitic infections such as PCP
  • amphotericin or trimethoprim in combination with sulfamethoxazole used to treat fungal and bacterial infections
  • probenecid is used to treat gout and similar conditions and is given together with certain antibiotics to make them more effective
  • methadone is used as a heroin substitute
  • vincristine, vinblastine, or doxorubicin, is used to treat cancer.
  • Tell your doctor if you are taking any of these.

Some medicines interact with Retrovir

These include:

  • clarithromycin, which is an antibiotic
  • phenytoin is used to treat epilepsy.
  • Tell your doctor if you are using clarithromycin or phenytoin. Your doctor may need to check you while you are using Retrovir.


If you are pregnant, become pregnant, or are planning to become pregnant:

  • Discuss with your doctor the risks and benefits of taking Retrovir.

If HIV -positive pregnant women take Retrovir, they are less likely to transmit the HIV infection to the fetus.

Retrovir and similar medicines can cause side effects in the fetus. If you have taken Retrovir during your pregnancy, your doctor may request regular blood tests and other diagnostic tests to check your baby’s development. For children with a mother who took NRTIs during pregnancy, the benefit of HIV protection outweighs the risk of side effects.


Women who are HIV -positive should not breastfeed because HIV infection can be transmitted to the baby through breast milk.

A small amount of the ingredients in Retrovir may also pass into breast milk.

If you are breast-feeding or planning to breast-feed:

  • Talk to your doctor immediately.

Driving and using machines

You are responsible for assessing whether you are fit to drive a motor vehicle or perform work that requires sharpened attention. One of the factors that can affect your ability in these respects is the use of drugs due to their effects and/or side effects. Descriptions of these effects and side effects can be found in other sections. Read all the information in this leaflet for guidance.

Retrovir may make you dizzy and have other side effects that make you less alert.

  • Avoid driving or using machines, if you feel unwell.

Retrovir contains sodium

This medicine contains less than 1 mmol (23 mg) sodium per dose unit, ie it is essentially ‘sodium-free’.

You will need to have regular blood tests

As long as you are taking Retrovir, your doctor will arrange regular blood tests to detect side effects. For more information on these side effects, see section 4 of this leaflet.

Keep in regular contact with your doctor

Retrovir helps you keep your disease under control but is not a cure for HIV infection. You must take it every day to prevent the disease from getting worse. You can still get other infections or diseases associated with HIV infection.

  • Keep in touch with your doctor, and do not stop taking Retrovir without your doctor’s advice.

Protect other people

HIV infection is spread through sexual contact with someone who has an infection or through infected blood (eg by splitting injection needles). You can still transmit HIV infection while taking this medicine, even though the risk of effective antiviral therapy is reduced.

Discuss with your doctor the necessary measures to avoid infecting others.

How to take Retrovir

Always take this medicine exactly as your doctor has told you. If you are not sure, talk to your doctor or pharmacist.

Capsules should be swallowed whole with water.

Retrovir is also available in liquid form.

How much Retrovir do you need to take?

Adults and adolescents weighing at least 30 kg:

The usual dose of Retrovir is 250 mg or 300 mg twice daily. Take the doses at 12-hour intervals.


Your child can take Retrovir in liquid form or 100 mg capsules.

Children weighing more than 21 kg and less than 30 kg:

The usual dose of Retrovir is two 100 mg capsules twice daily.

Children weighing at least 14 kg and less than or equal to 21 kg:

The usual dose of one of Retrovir is one 100 mg capsule in the morning and two 100 mg capsules in the evening.

Children weighing at least 8 kg and less than 14 kg:

The usual dose of Retrovir is one 100 mg capsule twice daily.

Capsules are not suitable for children weighing less than 8 kg. Your doctor may decide to give your child Retrovir in liquid form or as an injection instead.

Pregnancy, breast-feeding and newborns:

You should not normally take Retrovir during the first 14 weeks of pregnancy. After week 14, the usual dose is 500 mg every day, given as a 100 mg capsule five times daily, until labor begins. During labor and birth, your doctor may give you a Retrovir injection until the baby’s umbilical cord has been cut off. Your newborn baby can also be given Retrovir to protect themselves from becoming infected with HIV.

People with kidney or liver problems:

If you have severe kidney or liver problems, you may receive a lower dose of Retrovir depending on how well your kidneys or liver are working. Follow your doctor’s advice.

If you take more Retrovir than you should:

If you take more Retrovir than you should, contact your doctor or pharmacist for advice. Show the Retrovir package, if possible.

If you have ingested too much medicine or if e.g. If a child has ingested the medicine, contact a doctor or hospital for an assessment of the risk and advice.

If you forget to take Retrovir:

If you forget to take a dose of Retrovir, you do not need to worry. You can take your next dose as soon as you remember it up to two hours before the next dose. If it is less than two hours until you take your next dose, just skip the missed dose and take the next dose at the usual time. Then continue the treatment as usual.

Do not take a double dose to make up for a forgotten dose.

Do not stop taking Retrovir without your doctor’s advice

Take Retrovir for as long as your doctor prescribes it. Do not stop without seeking medical advice.

Possible side effects

During HIV treatment, weight gain and increased levels of lipids and glucose in the blood may occur. This is partly related to restored health and lifestyle, but when it comes to blood lipids, there can sometimes be a connection with HIV drugs. Your doctor will perform tests to find such changes.

Treatment with zidovudine (Retrovir) often causes loss of fat on the legs, arms, and face (lipoatrophy). It has been shown that such loss of body fat may not return completely when zidovudine treatment is stopped. Your doctor will look for signs of lipoatrophy. Tell your doctor if you notice that the amount of fat decreases on your legs, arms, and face. When such signs occur, stop taking Retrovir and receive other HIV treatment.

Like all medicines, this medicine can cause side effects, although not everybody gets them. Some side effects can be detected by blood tests and do not appear until 4-6 weeks after you start taking Retrovir. If you get any of these effects, and if they are serious, your doctor may advise you to stop taking Retrovir.

In addition to the side effects mentioned below, other conditions can also develop during combination therapy for HIV.

  • It is important to read the information under “Other possible side effects of combination therapy for HIV”.
Very common side effects are
 These may occur in more than 1 in 10 users of Retrovir: headache and nausea.
Common side effects are
 These can occur in up to 1 in 10 users of Retrovir:
 vomitingdiarrheaabdominal pain-dizziness muscle achesgeneral malaise. Common side effects that can be detected in your blood tests are low red blood cell count ( anemia ) or low white blood cell count ( neutropenia or leukopenia )increase in liver enzyme levels increase in the level of bilirubin (a substance produced by the liver) in the blood, which can yellow your skin.
Uncommon side effects are
 These can occur in up to 1 in 100 users of Retrovir: skin rash (red, swollen, or itchy)shortness of breathfeverwidespread aches, and pain flatulence _ _or impotence. Uncommon side effects that can be detected in your blood tests are decreastseveralr in blood cells involved in blood clotting capacity ( thrombocytopenia ), or a decrease in all types of blood cells (pancytopenia).
Rare side effects
 These side effects may affect up to 1 in 1,000 people in Retrovir:
 lactic acidosis (excess lactic acid in the blood, see next section, “Other possible side effects of combination therapy for HIV”)liver diseases, such as jaundice, enlarged liver or fatty liver inflammation of the pancreaschest pain, heart muscle diseaseseizuresdepression or general anxiety, difficulty sleeping, difficulty concentrating, drowsinesspoor digestion, loss of appetite, taste changesdiscoloration of the nails, skin or inside of the mouthful-like symptoms – chills, sweating and coughingnumbness and tingling in the skin increased urination frequency breast augmentation in men. A rare side effect that can be detected in your blood tests is decreased number of a type of red blood cell (pure red cell aplasia).
Very rare side effects
 A side effect that can occur in up to 1 in
 users of Retrovir, and what can be detected in blood samples is a failure in the production of new blood cells ( aplastic anemia ) in the bone marrow.
If you get any side effects
 Talk to your doctor or pharmacist. This also applies to side effects that are not mentioned in this information.
Other possible side effects are with combination therapy for HIV
 Some conditions can develop during HIV treatment.
Old infection can flare up
 Patients with advanced HIV infection ( AIDS ) have a weakened immune system and are more likely to develop serious infections (opportunistic infections ). When these patients start treatment, it happens that hidden infections can flare up and cause signs and symptoms of inflammation. These symptoms are probably caused by the body’s immune system getting better and the body starts to fight these infections.
In addition to these opportunistic infections, autoimmune diseases (conditions that occur when the immune system attacks healthy body tissue) can also occur after you start medication for your HIV infection. Autoimmune diseases can develop several months after the start of treatment. If you notice any symptoms of infection or other symptoms such as muscle weakness, a weakness that starts in the hands and feet and moves towards the torso, palpitations, tremors, or hyperactivity, contact a doctor immediately for necessary treatment.
If you notice any symptoms of infection while taking Retrovir: Talk to your doctor immediately. Do not take any other medicines for infection without consulting your doctor.
Lactic acidosis is a rare but serious side effect
 Some patients taking Retrovir to develop a condition called lactic acidosis, in combination with an enlarged liver. Lactic acidosis is caused by an accumulation of lactic acid in the body. This condition is rare; if it occurs, it develops after a few months of treatment. It can be life-threatening and causes failure of internal organs.
The risk of developing lactic acidosis is greater in patients who have liver disease, or in severe obesity, especially in women.
Characteristics of lactic acidosis include:
 deep, fast, strained breathing drowsiness numbness or feeling of weakness in arms and legs decreased appetite, weight loss nausea, vomiting abdominal pain.
During treatment, your doctor will closely monitor for signs of lactic acidosis. If you have any of the symptoms mentioned above, or other symptoms that worry you see your doctor as soon as possible.
You may have a skeletal problem
 Some patients treated with combination therapy for HIV develop a condition called osteonecrosis. In this condition, parts of bone tissue die due to reduced blood supply to the skeleton.
Patients may be at greater risk for this condition: if they have been treated with combination therapy for a long time they are also taking anti-inflammatory drugs called corticosteroids if they drink alcohol if their immune system is very weak they are overweight. Characteristics of osteonecrosis include stiffness in the joints aches and pains (especially in the hips, knees, or shoulders), and mobility impairment. If you notice any of these symptoms: Tell your doctor.
Other effects that can be detected with blood tests
 Combination therapy for HIV can also cause: elevated levels of lactic acid in the blood, which in rare cases can lead to lactic acidosis this can be demonstrated in the blood samples that will be taken while you are taking Retrovir.

How to store Retrovir

Keep this medicine out of the sight and reach of children.

Do not use this medicine after the expiry date which is stated on the carton after EXP. The expiration date is the last day of the specified month.

Do not store above 30 ° C (86 ° F).

Store in the original package.

Medicines should not be disposed of via wastewater or household waste. Ask your pharmacist how to dispose of medicines no longer required. These measures will help to protect the environment.

Contents of the pack and other information

Content declaration

The active substance is zidovudine. Each capsule contains 100 mg and 250 mg of zidovudine, respectively.

Other ingredients are:

Capsules : corn starch, microcrystalline cellulose, sodium starch glycolate, magnesium stearate, titanium dioxide (E171), gelatin, indigo carmine (E132) (only in 250 mg), opacode 10A1 black or 10A2 black (shellac, black iron oxide E172, propylene glycol only 28% ammonium opacode 10A1 black), strong ammonium solution (only in opacode 10A2 black), potassium hydroxide (only in opacode 10A2 black)).

Appearance and package sizes of medicines

Retrovir capsules 100 mg are hard, white capsules, marked with the code “GSYJU”. They are supplied in jars or blister packs of 100 capsules.

Retrovir capsules 250 mg are hard blue and white capsules marked with the code “GSJV2”. They are supplied in blister packs of 40 capsules.

Marketing Authorization Holder and Manufacturer:

ViiV Healthcare BV

Van Asch van Wijckstraat 55H

3811 LP Amersfoort


For any information about this medicine, please contact the local representative of the Marketing Authorization Holder:

GlaxoSmithKline AB

Box 516

169 29 Solna

Tel .: 08-638 93 00


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