Propeg 100mg Capsule is a medicine used to treat breast cancer. This medicine helps to slow down the growth and multiplication of cancer cells. Propeg 100mg Capsule should be taken as your doctor's advice. Your doctor will decide how much you need to take and for how much time. You may take it with or without food but better to take it at a fixed time. You should take this medicine for as long as it is prescribed for you. Common side effects of this medicine include headache, dizziness, weakness, and abdominal pain. Most of these are temporary and go away as soon as the body adjusts to the treatment. If any of these bothers you, let your doctor know. There may be ways of reducing or preventing them. It may cause irregular periods, bleeding, or spotting between menstrual periods. Inform your doctor if this occurs frequently. You should also inform the doctor immediately if you experience severe headaches, swelling in one leg, pain in breathing, or changes in vision or hearing. Your doctor should also know about all other medicines you are taking as many of these may make this medicine less effective or change the way it works. Pregnant and breastfeeding women should not take this medicine.