Hi, Just over a week ago I went to Dr, as neck was really painful. Have arthritis ( as well as under active thyroid ) Anyway, he arranged for me to go physio , and also gave me cocodamol. Said it was ok to take while on Naproxen. Within an hour of taking it, I had stomach pains, nausea, and then I passed out, on kitchen floor. When I came to, hubby was ringing for medics, but they sent ambulance as not sure if I banged my head. My blood pressure was high, nose bleed. They stayed till blood pressure normal. Told hubby to ring Drs. The duty Dr phoned back, said I should have just been told to take paracetamol. Checked on-line next day, found out that cocodamol should not be taken by people with under active thyroid. Fine now, though still got sore coccyx lol.