There is no single "most powerful" allergy medicine. The best allergy medicine for you depends on the severity of your allergies, your individual symptoms, and any other medical conditions you may have.
Intranasal corticosteroids are often considered the most effective treatment for seasonal allergies and are less likely than corticosteroid pills to cause significant side effects because they're not directly absorbed into the bloodstream.
Antihistamines, such as cetirizine (Zyrtec), loratadine (Claritin), and fexofenadine (Allegra), block the effects of histamine, a chemical released by the body during an allergic reaction. These medications can relieve symptoms such as sneezing, runny nose, and itchy eyes.
Decongestants like pseudoephedrine (PSE) can help relieve congestion by narrowing blood vessels in the nasal passages.
It's important to consult with a healthcare professional to determine the best allergy medicine for you. They can help you choose the most effective medication based on your individual needs and medical history.