Hello,
Welcome to the ehealthforum and I am really glad to help you out. The bitter taste on the skin can be due to more amount of sodium or salts being secreted in the sweat. When the water in the sweat evaporates, it leaves the salts (sodium, chloride and potassium) behind on your skin, which is why your skin tastes salty. If there is any excess of salts then it can give a bitter taste.Excess salty sweat is found in cystic fibrosis. Symptoms are salty tasting or bitter skin, constant coughing or large amounts of mucus and respiratory difficulty. In absence of any other factor, I advise you to consult a physician and discuss the possibility of cystic fibrosis with him.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care.