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Can antihistamines stop working over time?

Antihistamines do not lose their effectiveness over time or cause dependency. Some people may notice reduced effects due to higher exposure to allergens during peak allergy seasons. Switching to a different type of antihistamine can help if needed.

Key points:

• Antihistamines provide relief that lasts 4 to 24 hours depending on the type.
• They work quickly, often within 15 minutes to 3 hours.
• Increased allergen exposure can make effects seem weaker.
• Studies show consistent effectiveness in treating allergy symptoms over weeks.

This text has been fact-checked for accuracy by medino's clinical team.