Hay Fever Medicine in Japan: Allegra, Claritin, and Alesion Guide
A pharmacist's guide to OTC hay fever medicines available in Japan (Allegra FX, Claritin EX, Alesion 20), including ingredients, drowsiness, and how to buy them.
Hay Fever Medicine in Japan: Allegra, Claritin, and Alesion Guide
Itchy eyes, runny nose, endless sneezing — if this started soon after you arrived in Japan, you may have Japanese hay fever (kafun-shō).
From February through May, Japan sees heavy pollen releases from sugi (Japanese cedar) and hinoki (Japanese cypress) trees. It's common for visitors to develop symptoms here for the first time, even if they've never had allergies at home.
This guide covers the three main OTC hay fever medicines you can buy at Japanese pharmacies — without a prescription — from a pharmacist's perspective.
What Are Second-Generation Antihistamines?
Modern hay fever medicines are mostly "second-generation antihistamines." Compared to first-generation drugs, they cause less drowsiness and last longer.
Some of the most common OTC second-generation antihistamines sold in Japan are:
| Product Name | Active Ingredient | Daily Dose | OTC Class |
|---|---|---|---|
| Allegra FX | Fexofenadine | Twice daily | Class 2 |
| Claritin EX | Loratadine | Once daily | Class 2 |
| Alesion 20 | Epinastine | Once daily | Class 2 |
All three are Class 2 OTC medicines, which can be sold by either a licensed pharmacist (yakuzaishi) or a registered seller (toroku-hanbaisha) at a pharmacy or drugstore.
Allegra FX (Fexofenadine)
Best for: People who must stay alert — drivers, office workers, parents.
Allegra FX is the same molecule as Allegra sold worldwide, making it the most familiar option for many international visitors.
- 1 tablet, twice a day (morning and evening)
- Designed for very low drowsiness risk
- No warning against driving on the package insert
- For ages 15 and up
Can be taken with or without food, but avoid grapefruit juice, as it may affect absorption.
Claritin EX (Loratadine)
Best for: Once-daily convenience; visitors already familiar with Claritin.
Claritin, long available worldwide, became an OTC drug in Japan in 2017 and was reclassified from Class 1 to Class 2 OTC in 2021.
- 1 tablet, once a day, after a meal
- Low drowsiness
- For ages 15 and up
- Class 2 — sold by either a pharmacist or a registered seller
If you have underlying conditions or take other medicines, tell the pharmacist or registered seller at purchase. Look for a pharmacy with English-speaking staff, or use a translation app.
Alesion 20 (Epinastine)
Best for: People who want to take one pill at bedtime and be covered all day.
Alesion 20 was developed in Japan.
- 1 tablet, once a day, before bed
- Effect lasts roughly 24 hours
- For ages 15 and up
The "take it at night, forget about it" simplicity makes this a popular choice.
Drowsiness and Side Effects
Second-generation antihistamines cause less drowsiness than older drugs, but individual responses vary. Package inserts state:
- Allegra FX: No explicit driving restriction
- Claritin EX: Use caution when driving
- Alesion 20: Use caution when driving or operating machinery
If you're trying one of these for the first time, start on a day off or when you're staying home.
Other commonly reported side effects include dry mouth, mild headache, and mild stomach discomfort. If anything feels wrong, stop taking the medicine and consult a pharmacist or doctor.
How to Buy at a Japanese Pharmacy
Useful Japanese phrases
- Kafun-shō no kusuri ga hoshii desu. — "I'd like hay fever medicine."
- Nemuku naranai kusuri wa dore desu ka? — "Which one doesn't make you drowsy?"
- Ichinichi ikkai no mono ga ii desu. — "I'd prefer once-a-day medicine."
What to tell the pharmacist
- Any other medicines you're taking (especially other allergy or cold medicines)
- Pregnancy or breastfeeding
- Medical conditions (especially liver or kidney issues)
When to see a doctor instead
If symptoms are severe or last more than two weeks, consider visiting an ENT clinic (jibi-inkōka) for stronger prescription medicines, nasal sprays, or eye drops. With Japan's national health insurance, you pay only 30% of the cost.
Warning: Similar-Sounding Names
Japanese medicine names can differ by one character while containing different doses or even different ingredients. Always check both the product name and the active ingredient on the package.
- Allegra FX (fexofenadine, adult) ≠ Allegra Junior (children, same ingredient but different dose)
- Alesion 20 ≠ Alesion 10 (same ingredient, half the dose)
Frequently Asked Questions
Q. Can I bring my own hay fever medicine from home? A. Personal-use amounts (generally up to one month's supply) are allowed, but verify that no banned ingredients are included before traveling.
Q. Is it safe to take every day during pollen season? A. Daily use throughout pollen season (February–May) is standard. If symptoms don't improve, consult a doctor.
Q. Do masks help? A. Yes — masks reduce pollen intake. Japanese pharmacies also stock dedicated pollen-blocking masks, eye drops, and nasal sprays.
Sources
- Allegra FX package insert (Hisamitsu Pharmaceutical)
- Claritin EX package insert (Taisho Pharmaceutical)
- Alesion 20 package insert (SSP / Ssi)
- Pharmaceuticals and Medical Devices Agency (PMDA)
- Japan Ministry of Health, Labour and Welfare — OTC Drug Guidelines
Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult a licensed pharmacist or physician before taking any medication.