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Comparison of Common Over-the-Counter Antihistamines
You’re absolutely right to want to compare OTC antihistamines carefully, especially with concerns about drowsiness and potential long-term risks like dementia.
Here’s a comparison of four common antihistamines:
| Antihistamine | Brand Name(s) | Generation | Sedation | Duration | Dementia Risk? | Typical Use |
|---|---|---|---|---|---|---|
| Cetirizine | Zyrtec | 2nd Gen | Low–moderate | 24 hrs | No known link | Allergies, hives |
| Fexofenadine | Allegra | 2nd Gen | None–very low | 24 hrs | No known link | Allergies |
| Loratadine | Claritin | 2nd Gen | Very low | 24 hrs | No known link | Allergies |
| Diphenhydramine | Benadryl | 1st Gen | High | 4–6 hrs | Yes (with long-term use) | Allergies, sleep aid |
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✅ Safest to Use (Short and Long Term)
The second-generation antihistamines — ‘‘cetirizine’’, ‘‘fexofenadine’’, and ‘‘loratadine’’ — are generally safer for most people, especially for long-term use:
• They don’t cross the blood-brain barrier as easily, so they cause less drowsiness • No solid evidence links them to dementia • Often recommended by allergists for chronic allergy relief
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⚠️ Benadryl (Diphenhydramine): Use With Caution
‘‘Diphenhydramine’’ is a first-generation antihistamine. It’s effective, but:
• Strongly sedating • Shorter-acting, often requiring multiple doses per day • Linked in studies to increased risk of dementia when used regularly or long-term
(due to its strong anticholinergic effects)
• Sometimes misused as a sleep aid, especially in older adults — this is not recommended
The Beers Criteria, a guide used in geriatrics, advises against using diphenhydramine in older adults unless absolutely necessary.
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Summary
• Best for daily allergies: ‘‘Fexofenadine’’ (least sedating), ‘‘loratadine’’, or ‘‘cetirizine’’ • Avoid long-term use of Benadryl, especially in older adults or for sleep • If you’re older (65+) or have concerns about cognition, stick with second-generation options
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If you’d like help choosing the best one based on your symptoms (e.g., itchy eyes, runny nose, hives), I can help with that too.
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Let me know if you’d like this saved as a .txt file for upload to your DokuWiki installation.