In this literature review, we will introduce all reported methods that have been developed for determination of the antihistaminic drug, olopatadine HCl, the cough suppressant drug oxeladine citrate, and certain antihypertensive drugs such as amlodipine besylate and xipamide in their pure form, combined form with other drugs, combined form with degradation products, and in biological samples. We also will shed the light on the most important combination of drugs that are used for treatment of allergy and hypertension.

In this literature review, we will introduce all reported methods that have been developed for determination of the antihistaminic drug, olopatadine HCl, the cough suppressant drug oxeladine citrate, and certain antihypertensive drugs such as amlodipine besylate and xipamide in their pure form, combined form with other drugs, combined form with degradation products, and in biological samples. We also will shed the light on the most important combination of drugs that are used for treatment of allergy and hypertension.