I'm 46yrs and get terrible acne on my lower face and neck. took doxycycline for a mth. no help. what can i do?

Try benzoyl peroxide: You can try 2.5% benzoyl peroxide. Studies have shown that 2.5% works just as well as 5% benzoyl peroxide, with less side effects and irritation on your skin. You can buy these over the counter. If you have severe acne (cystic), you should see a dermatologist and discuss treatment options. They vary from either a combination or monotherapy of hormones, antibiotics, creams, steroid injections, etc