Hi, Next Choice contains levonorgestrel, a female natural sex hormone that acts as an emergency contraceptive pill and used in the prevention of unwanted pregnancies from unprotected sexual intercourses when taken within 72 hours after sexual encounters. It may cause sore throat or tonsillitis, symptoms of serious allergic reactions like itching, rashes, swelling of face, lips, tongue, hands or feet, blisters or ulcers on the skin, in the mouth or airways etc. Again, Zpack contains azithromycin that belongs to the group of antibiotics known as macrolides is used in the treatment of bacterial infections such as pneumonia, bronchitis, urinary tract infection, sexually transmitted diseases, sinus infections, infections of ears and eyes etc. Zpack may cause serious skin reaction such as fever, sore throat, swelling in lips, tongue or face, burning in eyes, blisters or ulcers in the mouth, airways or on the skin etc. If you notice such type of allergic reactions during taking these medications, then you should stop taking these medications and inform your doctor first for detecting the exact cause for your present sufferings. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Zubayer Alam, General And Family Physician