Suggest Remedy For Chronic Skin Rash On Back

I am trying to find out side effects for the drugs my husband is taking. He has a rash on his back that is driving him crazy...dermatologist has prescribed several different antibiotics, I have changed laundry detergents, we have used over the counter cortisone...nothing is helping. Dermatologist calls it an unspecified rash!!
The prescrips he is taking are:

Atorvastatin Tab 10 mg
Hydrochlorothiazide 50 mg
Metoprolol Succinate 100 mg
Clonidine Tab .2 mg
Amlodipine Tab 10 mg
Ramipril Cap 10 mg
Potassium CL TB 10 MEQ


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