Can I take 2 tablets of cetirizine hydrochloride extra strength 24h instead of 1?

Hello, the adult dose can be up to 10 mg in the morning and 10 mg in the evening It is suggested not to exceed 10 mg per day over the counter and it can go up to 20 mg per day under prescription So, under prescription, you can take 1 co of cetirizine extra strength in the morning and 1 co in the evening.The two major side effects that can increase with a higher intake are: headaches and drowsiness If your allergic symptoms persist, I suggest that you consult your local pharmacist or your doctor. There are more effective solutions, depending on your main symptoms, under prescription from the doctor or the pharmacist (behind the counter).