Amlodipine Benadryl Tablets I and II are different because the amount of amlodipine in the drug is different. Amlodipine Benadryl Tablet I contains 2.5 mg of Amlodipine and 10 mg of Benadryl Hydrochloride. On the other hand, Amlodipine Benadryl Tablet II is composed of Amlodipine 5 mg and Benadryl Hydrochloride 10 mg. Therefore, in comparison, Amlodipine Benadryl Tablet II is more effective in lowering blood pressure. Both Amlodipine Benadryl Tablets I and II are combination antihypertensive drugs and can be used in patients with high blood pressure who are unable to keep their blood pressure at the desired level by taking Amlodipine or Benadryl alone. Adverse reactions such as cough, dizziness, headache and edema may occur after taking the drugs. Contraindicated in patients with hypersensitivity to Benadryl or Amlodipine, renal failure, pregnancy. Amlodipine Benadryl tablets should be taken under medical supervision to avoid adverse effects.