Duovir N (150+200+300) mg is typically prescribed to treat HIV known to cause acquired immunodeficiency syndrome or AIDS. This medicine will, however, not cure the body of HIV or AIDS. It may also be prescribed for a condition that is not mentioned here. Lamivudine, Nevirapine and Zidovudine are the active ingredients present in this antiviral medicine. The drug belongs to a group of HIV medications known as reverse transcriptase inhibitors that do not allow HIV to multiply in the body.

Take medicine strictly as per the advice of your doctor or the instructions on the drug label. Do not change the dosage of the medicine unless your doctor tells you to do so. Also, make sure that you do not take medicine even after the prescribed time is over. 

Avoid the drug if you are allergic to any ingredients or any medicine containing zidovudine, lamivudine, or emtricitabine. Also, do not take the drug with other medications that contain lamivudine or zidovudine. Inform your doctor if you use any of these drugs such as ganciclovir, anti-cancer medicines such as interferons, doxorubicin, or sulfa drugs. There may be other drugs as well that may interact with the medicine.

• It has been seen that some people who took medicine experienced lactic acidosis. The symptoms of lactic acidosis may deteriorate with time and prove dangerous. Therefore, you must seek medical attention on the first signs of lactic acidosis, such as pain or weakness in the muscles, numb limbs, breathing issues, stomach pain, or nausea.
• The drug may lead to serious liver damage. Consult your doctor if you suffer from any of the following symptoms such as severe pain in the upper stomach that spreads to the back, nausea, vomiting, fast heartbeats, loss of appetite, itching, clay-colored stools, dark urine, or jaundice.
• The medicine can reduce the count of white blood cells, a component in the blood that equips the body to fight off infections. It is essential that you take proper precautions to avoid getting infections. Stay away from sick people and avoid activities that increase the risk of bleeding. 
• It is an FDA pregnancy category C drug. It is not yet proved if it can harm an unborn baby. The virus can be transmitted to the baby if the mother is not treated properly during pregnancy. The drug may get into breast milk and cause harm to a nursing baby. Avoid the medication if you are breastfeeding. Keep in mind to inform your doctor if you are pregnant or planning to have a baby soon or are breastfeeding. 
• For people who have hepatitis B, you may develop liver symptoms when you stop taking medicine. These symptoms may be visible for months after you stop taking the drug. 
• Inform your doctor if you suffer from any conditions such as kidney disease, bone marrow suppression, or if you have used other HIV drugs in the past.
• It is important to keep all the precautions in mind before you take the drugs. Make sure to discuss everything with your doctor and clear all your doubts that you may have about the drug.

• Some side effects of the medicine include drowsiness, headache, vomiting, dizziness, nausea, or diarrhea. If any of the symptoms continue for long, consult your doctor immediately. In some people, there may be a deterioration of a previous medical ailment or the development of a new one due to changes in their immune system. Inform your doctor immediately if any such thing happens.
• Some people develop lactic acidosis. The initial symptoms of the condition may deteriorate with time and can prove to be dangerous. Some initial symptoms are weak muscles, numbness in the limbs, breathing troubles, stomachache, or nausea with vomiting.
• The medication can lead to severe damage to your pancreas or liver. Consult your doctor right away if you experience any symptoms such as severe pain in the upper stomach, which advances to the back, nausea and vomiting, fast heartbeats, itching, loss of appetite, dark urine, clay-colored stools, or jaundice.
• There may be other side effects too that you may experience. Consult your doctor immediately if you notice any such things.