Japan’s approach to medication regulation is notably stringent compared to many Western countries.
The Pharmaceutical Affairs Law (officially the Act on Securing Quality, Efficacy and Safety of Products Including Pharmaceuticals and Medical Devices) serves as the primary legislative framework governing medications in Japan.
Understanding Japan’s Medication Import Laws
Overview of Japan’s Pharmaceutical Affairs Law
The Pharmaceutical Affairs Law strictly regulates which medications can enter Japan, regardless of their legal status in other countries.
This comprehensive legislation aims to protect public health by ensuring all pharmaceuticals in Japan meet specific safety and efficacy standards.
Under this law, many medications that are available over-the-counter in countries like the United States or the UK may be:
- Completely prohibited in Japan
- Available by prescription only
- Restricted in quantity for personal imports
- Subject to different formulation requirements
The law is enforced by Japanese Customs officials who have the authority to inspect, confiscate, or deny entry to medications that don’t comply with regulations.
Categories of Restricted Medications
Japanese regulations categorize imported medications into several groups:
| Category | Description | Examples | Import Requirements |
|---|---|---|---|
| Prohibited Substances | Completely banned medications | Products with stimulants, narcotics, or certain psychoactive compounds | Cannot be imported under any circumstances |
| Prescription Medications | Medications requiring doctor oversight | Many antibiotics, stronger pain relievers | Requires Yunyu Kakunin-sho (import certificate) |
| Quasi-Drugs | Lower-risk medicinal products | Some topical treatments, medicated soaps | Generally allowed in limited quantities |
| OTC Medications | Non-prescription drugs | Basic pain relievers, some allergy medications | Limited quantities allowed without special permission |
General Rules for OTC Medications
For over-the-counter medications like Benadryl, Japan typically allows:
- Personal use only: The medication must be clearly for your own medical needs, not for distribution or sale
- Reasonable quantity: Generally limited to amounts consistent with personal use
- Proper declaration: All medications must be declared at customs
- Original packaging: Medications should remain in their original containers with labeling intact
Two-Month Personal Supply Rule
One of the most important regulations to understand is Japan’s “two-month supply” rule:
“A visitor may bring into Japan a two-month supply of over-the-counter medications for personal use without special permission.”
This is a critical threshold for travelers to understand. Exceeding this limit can trigger additional scrutiny and potentially require formal import documentation.
For medications taken daily, calculate exactly how many pills constitute a two-month supply based on your dosage to avoid complications.
Prohibited Active Ingredients
Japan maintains a list of specific active ingredients that are either banned or heavily restricted. Some common ingredients in international formulations that may cause problems include:
- Pseudoephedrine: Found in many cold and sinus medications
- Codeine: Present in some cough medicines and pain relievers
- Dextromethorpan (in quantities exceeding Japanese standards)
- Stimulants like ephedrine
- Certain antihistamines in concentrations higher than Japanese regulations permit
This is particularly relevant for Benadryl, as some formulations (especially combination products) may contain restricted ingredients alongside diphenhydramine.
Process for Verification
Before traveling to Japan with any medication, including Benadryl, follow this verification process:
- Check the active ingredients in your specific Benadryl formulation
- Compare against Japan’s prohibited substances list (available on the Ministry of Health, Labour and Welfare website)
- Calculate the exact quantity needed for your stay (staying within the two-month supply limit)
- Prepare documentation showing the medication’s ingredients and your need for it
- Consider alternatives available in Japan if your specific formulation raises concerns
For medications that require special permission, you’ll need to apply for a Yunyu Kakunin-sho (import certificate) through Japan’s Ministry of Health, Labour and Welfare—a process that typically takes 2-4 weeks and requires detailed documentation from your physician.
Is Benadryl Legal in Japan?
When planning a trip to Japan, understanding the legal status of your medications is crucial. Benadryl is a common concern for many travelers, and the answer to whether it’s legal in Japan requires some nuance.
Legal Status of Diphenhydramine in Japan
Diphenhydramine, the active ingredient in Benadryl, is not inherently illegal in Japan. In fact, it’s available in certain Japanese medications.
However, Japan’s pharmaceutical regulations differ significantly from countries like the United States, and this creates complexity for travelers.
The Japanese government classifies medications through the Pharmaceutical Affairs Law, which categorizes substances based on their ingredients, potency, and intended use.
While diphenhydramine itself is permitted, certain formulations or combinations with other ingredients may be restricted or prohibited.
Japan maintains a strict stance on medications containing stimulants, narcotics, or psychotropic substances. The Ministry of Health, Labour and Welfare (MHLW) regulates these substances to prevent misuse and protect public health.
Different Benadryl Formulations and Their Legality
Not all Benadryl products are created equal, and this distinction matters greatly when traveling to Japan:
| Benadryl Formulation | Legal Status in Japan | Notes |
|---|---|---|
| Benadryl Allergy (diphenhydramine only) | Generally permitted | Limited to personal use quantities (2-month supply) |
| Benadryl Allergy & Cold (with pseudoephedrine) | Prohibited | Contains a controlled substance in Japan |
| Benadryl Allergy Plus Congestion | May be restricted | Depends on specific formulation |
| Children’s Benadryl | Generally permitted | Similar to adult version if only containing diphenhydramine |
| Benadryl Topical Creams/Gels | Generally permitted | Check specific ingredients |
The key issue is that many Benadryl products sold in the US and other countries contain additional active ingredients beyond diphenhydramine.
Products containing pseudoephedrine (a decongestant) are strictly prohibited in Japan without special permission, as this substance is controlled due to its potential use in manufacturing illegal drugs.
Japanese Equivalents to Benadryl
If you’re concerned about bringing Benadryl to Japan, you might consider purchasing local alternatives after arrival:
- Drewell (ドリエル): Contains diphenhydramine and is marketed as a sleep aid
- Naron Ace (ナロンエース): Contains diphenhydramine among other ingredients
- Allegra (アレグラ): Different active ingredient (fexofenadine) but treats similar allergy symptoms
- Alesion (アレジオン): Different active ingredient (epinastine) for allergy relief
These medications are available at Japanese pharmacies (called “drugstores” or “yakkyoku” in Japanese). However, formulations may differ from what you’re accustomed to, and language barriers can make identifying appropriate alternatives challenging.
Real Traveler Experiences with Bringing Benadryl to Japan
Traveler experiences with bringing Benadryl to Japan vary considerably:
“I brought a small bottle of Benadryl tablets in their original packaging with my other toiletries. Customs never even asked about them.” – American tourist, 2022
“When I declared my medications at customs, the officer examined my Benadryl Allergy & Cold, saw it contained pseudoephedrine, and confiscated it immediately. I wish I had checked beforehand.” – Canadian visitor, 2021
“I brought a doctor’s note explaining my need for Benadryl and showed it at customs. The officer appreciated the documentation and allowed me to keep my medication.” – British traveler, 2023
These anecdotes highlight the importance of preparation and transparency. Most travelers report no issues when bringing small amounts of original Benadryl (diphenhydramine-only formulations) for personal use, especially when accompanied by appropriate documentation.
Enforcement Variability at Customs
Japanese customs enforcement regarding medications can vary significantly:
- Airport of Entry: Major international airports like Narita or Haneda may have more consistent enforcement than smaller regional airports.
- Customs Officer Discretion: Individual officers may exercise different levels of scrutiny.
- Declaration Practices: Travelers who proactively declare medications generally report more positive experiences than those who attempt to bring medications without disclosure.
- Documentation Impact: Having a doctor’s note, prescription, or Yakkan Shoumei (medication import certificate) significantly increases the likelihood of successful importation.
- Packaging Considerations: Medications in original packaging with clear labeling fare better than loose pills or repackaged medicines.
While some travelers report bringing Benadryl into Japan without any issues, others have had their medications confiscated. This inconsistency makes proper preparation essential for those who rely on these medications.
The bottom line: Standard Benadryl containing only diphenhydramine is generally legal to bring to Japan in limited quantities for personal use. However, Benadryl formulations containing additional active ingredients, particularly pseudoephedrine, are prohibited and likely to be confiscated.
Required Documentation for Bringing Medications to Japan
When traveling to Japan with medications like Benadryl, proper documentation is essential to ensure a smooth entry through customs.
Japanese authorities take medication imports seriously, and being prepared with the right paperwork can make the difference between keeping your medication or having it confiscated.
Doctor’s Notes and Prescriptions
A doctor’s note or prescription serves as official validation that you require the medication for legitimate medical purposes. For Benadryl or other diphenhydramine products, consider the following:
- Obtain a signed letter from your physician clearly stating:
- Your full name and date of birth
- The medical condition being treated
- The name of the medication (both brand name and generic)
- Dosage instructions
- Duration of treatment
- Confirmation that the medication is for personal use
Even though Benadryl is available over-the-counter in many countries, having a doctor’s note provides additional legitimacy when questioned by customs officials.
Packaging Requirements
Japanese customs officials need to clearly identify what medications you’re bringing into the country:
- Keep medications in their original packaging with visible labels showing:
- Brand name
- Generic name (diphenhydramine)
- Dosage information
- Manufacturer details
- Never transfer medications to unlabeled containers or pill organizers for travel
- Consider bringing the original receipt if you purchased the medication recently
- If possible, maintain the medication’s box with the list of ingredients clearly visible
Translation Recommendations
Language barriers can complicate the customs process, so translations are highly recommended:
- Translate your doctor’s note into Japanese if possible
- Prepare a simple document listing the active ingredients in Japanese (ジフェンヒドラミン for diphenhydramine)
- Use a professional translation service rather than machine translation for important medical documents
- Consider having a digital and physical copy of all translations
- Include the English name alongside Japanese translations for easy cross-reference
A properly translated medication list demonstrates respect for Japanese regulations and facilitates easier inspection by customs officials.
Yunyu Kakunin-sho Application Process for Larger Quantities
If you’re bringing more than a one-month supply of Benadryl or if you’re concerned about potential issues at customs, applying for a Yakkan Shoumei (薬監証明) or Yunyu Kakunin-sho (輸入確認書) is recommended:
- Download the application form from the Ministry of Health, Labour and Welfare website
- Complete the application with details about:
- Your personal information
- Travel dates
- Medication details (name, quantity, ingredients)
- Your medical condition
- Submit the following documents to the appropriate Regional Bureau of Health and Welfare:
- Completed application form
- Copy of prescription or doctor’s note
- Document showing the ingredients (package insert or similar)
- Submit at least two weeks before arrival in Japan
- Receive approval certificate to present at customs
For most travelers bringing a reasonable amount of Benadryl for personal use, this process may not be necessary, but it provides the highest level of assurance for entry.
Declaration Procedures at Customs
Proper declaration is crucial when bringing medications like Benadryl into Japan:
- Always declare medications on your customs declaration form
- Be proactive in showing your medications to customs officials
- Present all documentation (doctor’s note, prescriptions, Yunyu Kakunin-sho if applicable)
- Answer questions honestly about your medication’s purpose and quantity
- Remain patient and cooperative during inspection
Pro Tip: Keep all medication-related documentation in a single, easily accessible folder to streamline the customs process.
Remember that customs officials have discretion in enforcing regulations. Being transparent, organized, and prepared with proper documentation significantly increases your chances of bringing Benadryl into Japan without issues.
Understanding Benadryl Import Restrictions in Japan
When bringing Benadryl to Japan, understanding the specific restrictions around quantities, formulations, and ingredients is crucial for a trouble-free experience.
Japan’s pharmaceutical regulations are notably strict, and even common medications like Benadryl can cause issues if you’re not prepared.
Maximum Allowed Quantities
Japan’s medication import policy follows a “reasonable amount for personal use” principle, which generally translates to:
- Standard allowance: A 1-month supply for most medications
- Extended allowance: Up to a 2-month supply may be permitted if your stay warrants it
- Quantity limits: For Benadryl specifically, bringing 1-2 standard-sized bottles or blister packs (approximately 24-48 tablets) is typically considered reasonable
Exceeding these quantities may trigger additional scrutiny at customs and could be interpreted as importing for distribution rather than personal use, which is prohibited without proper licensing.
Differences Between Pill, Liquid, and Other Formulations
The formulation of Benadryl you bring can impact its legality in Japan:
- Tablets/pills: Generally the safest option, as ingredients are clearly listed and quantities are easily counted
- Liquid formulations: May face more scrutiny due to volume restrictions on liquids in carry-on luggage and potential additional ingredients
- Gel capsules: Acceptable but should be in original packaging
- Topical creams: Benadryl creams may contain different active ingredients than oral formulations, requiring separate verification
- Children’s formulations: Often contain different concentrations or additional ingredients that may be restricted
Important note: Always keep medications in their original packaging with clearly visible ingredient lists to facilitate customs inspection.
Combination Medications to Avoid
Many Benadryl products contain additional active ingredients that may be prohibited in Japan:
- Benadryl-D or formulations with pseudoephedrine are strictly prohibited
- Combination cold/flu medications containing stimulants or codeine
- Benadryl Plus products that include pain relievers or decongestants
- Night-time/PM formulations with additional sleep aids beyond diphenhydramine
- Allergy-sinus combinations with multiple active ingredients
These combination products have a high likelihood of being confiscated at Japanese customs due to their restricted ingredients.
Active Ingredients That Trigger Restrictions
Japan’s Pharmaceutical Affairs Law restricts several ingredients commonly found in Western over-the-counter medications:
| Ingredient | Status in Japan | Found in |
|---|---|---|
| Pseudoephedrine | Prohibited | Benadryl-D, Benadryl Allergy & Sinus |
| Codeine | Highly restricted | Some Benadryl cough formulations |
| Dextromethorphan (in high doses) | Restricted | Some Benadryl cough products |
| Phenylephrine (in certain concentrations) | May be restricted | Some Benadryl congestion formulas |
While diphenhydramine (Benadryl’s primary active ingredient) is generally permitted, these additional ingredients can cause your medication to be seized.
Checking Ingredients List for Compliance
Before packing Benadryl for Japan, follow these steps to ensure compliance:
- Examine the active ingredients list on your Benadryl packaging
- Verify that diphenhydramine is the only active ingredient (or check that any additional ingredients aren’t on Japan’s restricted list)
- Check the concentration of diphenhydramine (typically 25mg or 50mg per dose is acceptable)
- Photograph or document the ingredients list to show customs officials if questioned
- Consider Japanese alternatives like “Drewell” that contain the same active ingredient if your formulation might be problematic
“The key to avoiding issues at Japanese customs is to bring only simple, single-ingredient diphenhydramine products rather than combination formulations that may contain restricted substances.” – Travel health specialist recommendation
Being thorough in checking your medication’s ingredients before travel can prevent the stress and inconvenience of having your allergy medication confiscated upon arrival in Japan.
Japanese Alternatives to Benadryl and Where to Find Them
Japan offers several antihistamine options that function similarly to Benadryl, though they may contain different active ingredients or dosages.
Understanding these alternatives and knowing where to purchase them can be invaluable if you run out of medication during your trip or if your Benadryl is confiscated at customs.
Japanese Equivalents to Benadryl
While Benadryl as a brand isn’t commonly found in Japan, medications containing diphenhydramine (the active ingredient in Benadryl) are available under different names:
- レスタミンコーワ (Restamin Kowa) – Contains diphenhydramine and is one of the closest equivalents to Benadryl
- アレルギール (Allegill) – Another diphenhydramine-based antihistamine
- ドリエル (Drewell) – A sleep aid containing diphenhydramine
Other popular antihistamines in Japan include:
- アレグラ (Allegra) – Contains fexofenadine
- アレジオン (Alesion) – Contains epinastine
- ジルテック (Zyrtec) – Contains cetirizine
- クラリチン (Claritin) – Contains loratadine
Note: Japanese antihistamines may have different dosages or additional ingredients compared to their Western counterparts. Always check the active ingredients and consult with a pharmacist before use.
Where to Buy Antihistamines in Japan
Antihistamines can be purchased at various locations throughout Japan:
- 薬局/ドラッグストア (Yakkyoku/Drug Stores) – Dedicated pharmacies and drugstores
- コンビニ (Convenience Stores) – Limited selection of basic medications
- スーパーマーケット (Supermarkets) – Some larger supermarkets have pharmacy sections
For stronger medications or those containing diphenhydramine, you’ll typically need to visit a proper pharmacy rather than a convenience store.
Common Japanese Pharmacy Chains
Japan has several major pharmacy chains where you can reliably find antihistamines:
| Pharmacy Chain | Japanese Name | Notes |
|---|---|---|
| Matsumoto Kiyoshi | マツモトキヨシ | Largest chain, found in most cities and tourist areas |
| Welcia | ウエルシア | Widespread throughout Japan |
| Sundrug | サンドラッグ | Common in urban areas |
| Tsuruha Drug | ツルハドラッグ | Popular in northern Japan |
| Cosmos | コスモス | Common in western Japan |
Matsumoto Kiyoshi (recognizable by its distinctive blue and yellow signage) is particularly tourist-friendly, with many locations in major cities having staff who speak some English.
Language Barriers When Purchasing Medication
Navigating Japanese pharmacies can be challenging if you don’t speak the language. Here are some helpful strategies:
- Look for pharmacies with the “Tax-Free” sign – These often have English-speaking staff
- Use translation apps like Google Translate or images of your medication
- Learn basic pharmacy-related Japanese phrases:
- “アレルギー薬はどこですか?” (Where are the allergy medications?)
- “これと同じ薬はありますか?” (Do you have something similar to this?)
- “英語を話せる薬剤師はいますか?” (Is there a pharmacist who speaks English?)
Many urban pharmacies have staff with basic English skills, particularly in tourist areas. In more rural locations, bringing pictures of your medication or its active ingredients can be helpful.
Prescription vs OTC Options in Japan
Japan categorizes medications differently than many Western countries:
- 第一類医薬品 (Category 1) – Highest risk OTC medications; requires pharmacist consultation
- 第二類医薬品 (Category 2) – Medium risk; pharmacist consultation recommended
- 第三類医薬品 (Category 3) – Lower risk; no consultation required
- 処方箋医薬品 (Prescription Medications) – Requires a doctor’s prescription
Most diphenhydramine products fall under Category 1 or 2, meaning you’ll need to speak with a pharmacist to purchase them. The pharmacist will ask about your symptoms, allergies, and current medications before selling you the product.
If you need prescription-strength antihistamines, you’ll need to visit a Japanese doctor for a consultation. Many tourist areas have international clinics where English is spoken. Major cities also have specialized medical facilities for foreigners, such as:
- Tokyo Medical and Surgical Clinic (Tokyo)
- St. Luke’s International Hospital (Tokyo)
- Raffles Medical Clinic (Osaka)
Important: Japan’s national health insurance doesn’t cover tourists, so be prepared to pay out-of-pocket for medical consultations, which typically range from ¥5,000-¥10,000 ($35-$70 USD) for a basic visit.
By familiarizing yourself with Japanese alternatives to Benadryl and knowing where to find them, you can ensure you’re prepared for any allergy issues that might arise during your trip to Japan.
Risks of Non-Compliance: Penalties for Bringing Prohibited Medications to Japan
Japan takes its pharmaceutical regulations very seriously, and travelers should be aware of the potential consequences of non-compliance. Understanding these risks can help you appreciate why proper preparation before your trip is essential.
Potential Penalties for Undeclared Medications
When entering Japan, all travelers are legally required to declare medications they’re bringing into the country. Failing to declare medications—especially those containing controlled substances—can result in significant penalties.
Japanese customs officials are trained to identify potential medication violations and regularly conduct thorough inspections of travelers’ belongings.
The severity of penalties depends on several factors:
- The specific medication and its legal status in Japan
- The quantity being imported
- Whether there appears to be intent to distribute
- If proper documentation is missing
- Previous violations or criminal history
Confiscation Procedures
If customs officials discover undeclared or prohibited medications, the immediate consequence is confiscation. The process typically follows these steps:
- The medication is identified and documented by customs officials
- The traveler is questioned about the purpose and origin of the medication
- Officials determine whether the medication violates import regulations
- If deemed illegal or improperly documented, the medication is seized
- A confiscation receipt may be provided
“Having my medication confiscated in a foreign country was not only inconvenient but also potentially dangerous for my health condition. I wish I had researched Japan’s regulations beforehand.” – Anonymous traveler
Fines and Legal Consequences
Violations of Japan’s Pharmaceutical Affairs Law can result in:
- Monetary penalties ranging from ¥10,000 ($70) for minor infractions to several million yen for serious violations
- Criminal charges for importing significant quantities of controlled substances
- Detention during investigation if officials suspect intent to distribute
- Deportation in severe cases
For medications like modified Benadryl formulations containing stimulants or other controlled substances, penalties can be particularly harsh, as these may be classified under Japan’s strict anti-stimulant laws.
Impact on Entry Permission
Beyond immediate penalties, medication violations can affect your:
- Current entry status: Officials may deny entry even after you’ve arrived at a Japanese airport
- Future visa applications: A record of pharmaceutical violations can make obtaining future visas difficult
- Travel record: Immigration violations are recorded in international databases, potentially affecting travel to other countries
Real Cases of Travelers Facing Issues
While Japanese authorities don’t regularly publish statistics on medication confiscations, several notable cases have been reported:
| Year | Incident | Outcome |
|---|---|---|
| 2019 | American tourist with ADHD medication (Adderall) | 19-day detention before release following diplomatic intervention |
| 2020 | European traveler with prescription pain medication containing codeine | Medication confiscated, fined ¥50,000, allowed entry |
| 2021 | Canadian with undeclared antihistamines containing pseudoephedrine | Medication confiscated, warning issued, allowed entry |
| 2022 | Australian with over-the-counter sleep aids containing diphenhydramine | No issues after providing doctor’s letter explaining medical necessity |
These cases highlight the variable enforcement of medication import laws. While some travelers face serious consequences, others may receive only warnings—but this unpredictability itself is reason enough to ensure complete compliance.
Remember: Even common medications like certain formulations of Benadryl that contain additional active ingredients beyond diphenhydramine might trigger scrutiny. The safest approach is always to verify, document, and declare any medications you plan to bring to Japan.
Official Resources for Medication Verification
When planning to bring Benadryl or any medication to Japan, consulting official resources is essential for the most accurate and up-to-date information.
Japanese regulations regarding imported medications can change, and enforcement may vary, making official verification a crucial step in your travel preparations.
Japanese Ministry of Health, Labour and Welfare Resources
The Ministry of Health, Labour and Welfare (MHLW) is the primary authority on medication regulations in Japan. Their website offers comprehensive guidance specifically designed for travelers:
- Pharmaceutical Affairs Law Q&A Page – Contains detailed information about bringing medications into Japan
- Yakkan Shoumei Application Forms – Downloadable forms for the medication import certificate
- Prohibited Substances List – Regularly updated database of restricted and controlled substances
The MHLW provides detailed guidelines in multiple languages, including English, making it accessible for international travelers. Their resources include specific quantity limitations, documentation requirements, and application procedures for importing medications.
Embassy and Consulate Services
Japanese embassies and consulates worldwide offer invaluable assistance regarding medication import regulations:
- Pre-travel medication verification services
- Document authentication and certification
- Guidance on completing Yakkan Shoumei applications
- Information sessions and consultations for travelers with medical needs
Many embassies provide dedicated health and travel sections on their websites with country-specific guidance. For medications like Benadryl that contain diphenhydramine, embassy staff can often provide clarity on specific formulations available in your country and their legal status in Japan.
Online Verification Tools
Several official online tools can help verify the status of specific medications:
- PMDA (Pharmaceuticals and Medical Devices Agency) Database – Searchable database of approved medications in Japan
- Japan Customs Website – Interactive tool for checking restricted items
- MHLW Online Verification Portal – System for checking if your specific medication requires a Yakkan Shoumei
These digital resources allow you to search by active ingredient (diphenhydramine), brand name, or medication category to determine import requirements before travel.
Pre-Travel Consultation Options
For personalized guidance, consider these pre-travel consultation options:
| Consultation Type | Benefits | When to Use |
|---|---|---|
| Embassy Phone Consultation | Direct answers to specific questions | 1-2 months before travel |
| MHLW Email Service | Written documentation of advice | 2-3 months before travel |
| Consulate In-Person Meeting | Assistance with complex medication needs | For travelers with multiple medications |
| Japan Visitor Hotline | 24/7 multilingual support | For urgent inquiries |
Pre-travel consultations are particularly recommended for travelers with complex medical needs or those bringing multiple medications including Benadryl.
Contact Information for Inquiries
Keep these important contact details handy when planning your trip:
- MHLW Pharmaceutical Safety Division
- Email: [email protected]
- Phone: +81-3-3595-2400
- Japan Visitor Hotline (24/7 multilingual support)
- Phone: +81-50-3816-2787
- Nearest Japanese Embassy or Consulate
- Find contact information on the Ministry of Foreign Affairs website
When contacting these resources about bringing Benadryl to Japan, be prepared to provide:
- The exact brand name and formulation
- Active ingredients and their amounts
- Total quantity you plan to bring
- Duration of your stay in Japan
Reaching out to these official channels well in advance of your trip will ensure you have accurate information and sufficient time to prepare any required documentation for bringing Benadryl or other medications to Japan.