I started taking 20 mg periostat doxycycline hyclate to treat my ...

I started taking 20 mg periostat doxycycline hyclate to treat my acne. Prescription cream (retinol A) was not working 100% because acne on my chin kept coming back. I find this med to be very harsh on my stomach, i felt some sort of nausea from time to time. I drank at least 2 cups of water after taking it and also took it with food. After 10 days, I couldn't continue. I don't know if I should have taken it longer, maybe twice a day (instead of once) but my acne is now back. I am going back to see my dermatologist for alternatives. I also noticed that combined with my birth control pill, I had some sort of need to urinate more frequently.