Hi, Duromine contains phentermine which is an amphetamine like prescription medication used to suppress appetite. It can help weight loss by decreasing your hanger or making you feel full longer. Duromine or phentermine belongs to the group of medications known as anorectics that works by decreasing appetite. It should be used for a limited period of time to spread weight loss in overweight people who are exercising and eating a low calorie diet. Side effects of Duromine are common cold, stuffy and runny nose, cough, bronchitis, throat irritation, fever etc. HCG injection contains Human Chorionic Gonadotropin. It is a hormone that supports the normal development of an egg in the ovary of a woman. It stimulates the release of the egg during ovulation. HCG injection is used to cause ovulation and to treat infertility in women and to increase sperm count in men. Side effects of HCG injection are common cold, fever, bronchospasm, trouble breathing, decreased lung function, a partial or complete collapse of the lung airways called atelectasis etc. Both HCG injection and Duromine can cause common cold, flu like symptoms etc. Both of them have no interactions with your flu medications like amoxicillin, loratadine or benadryl. So, both HCG injection and Duromine are not contraindicated with your flu medications. You shouldn t stop taking both HCG injection and Duromine without consulting your doctor. Take care. Hope I have answered your questions. Let me know if I can assist you further. Regards, Dr. Zubayer Alam, General And Family Physician