It is used to treat Fever, Muscle spasms/pain.This medicine is used in treatment of extreme ongoing pain, E.g., due to cancer. Fentanyl is a family of medications called opioid painkiller. It operates in the brain to adjust the body's sensation and pain response.DosageUsually, the patch is changed every 72 hours. Apply to a new region every time to prevent discomfort. Before adding a new patch, please remove the old patch. The patch still contains enough fentanyl to pull it halfway up the sticky side and discard it properly.Use your doctoras regular schedule, not as sudden (breakthrough) pain as necessary. Use the drug.It can take up to 24 hours before fentanyl patches have pain relief. Other pain relievers can also be prescribed (such as acetaminophen, ibuprofen). Ask your doctor or pharmacist for fentanyl with other medicines safely.IndicationsUse your doctor's instructions for this drug to the skin. Do not use on skin exposed to radiation on burns, wounds, irritated skin, or (x-ray treatment). Choose a dry, hairless area, such as the chest, side, back, or upper arms, on a flat part of your body. For young children and people who cannot think clearly (for example, because of dementia), use the upper back patch to minimize the risk that it will be removed or inserted in the mouth.Use scissors to clip the hair closer to the skin if the skin is hairy. Do not shave hair as skin irritation can be induced. Use water to purify the area if necessary. On the application site, do not use soap, oils, lotions, or alcohol. Before you apply the patch, dry the skin well.The dose is focused on your health and treatment response. Do not use more than guided patches; adjust them more often or use them longer than recommended.