What Is an INN and How to Find a Drug's Real Name

Evgeny Yudin

Author

Qualification: International Health Access Consultant
Post: Founder of Pillintrip.com
Company: Pillintrip.com – International Health and Travel

Added: May 11, 2025

Changed: May 19, 2025

Introduction: Why Knowing a Drug's International Name Matters

Imagine this: you’re on vacation abroad, feeling unwell, and you walk into a local pharmacy—only to realize that none of the medicine names look familiar. Where’s "Nurofen" or "Panadol"? The answer: many medications go by different brand names in different countries. That’s where the International Nonproprietary Name, or INN, comes to the rescue.

An INN is a universal, officially recognized name for the active ingredient in a medicine. It’s the standard name used around the world, regardless of local brand variations. If you know the INN, you can find the right medication almost anywhere.

In this article, we’ll explain what an INN is, why it’s useful, how to find it, and why it’s important to verify it using reliable sources.

Let’s break it down step by step.

What Is an INN: A Simple Explanation

An International Nonproprietary Name (INN) is the official, globally recognized name for a medicine’s active substance. It’s not a brand name or a marketing term—it’s the scientific name that health professionals and researchers use to avoid confusion across countries and languages.

For example:

Ibuprofen is the INN, while Nurofen or Advil are brand names.
Paracetamol (or acetaminophen in the U.S.) is the INN, while Panadol and Tylenol are brand names.

INNs are assigned and managed by the World Health Organization (WHO). Each INN is unique and intended to be used worldwide, no matter where the medicine is sold. These names are designed to be easy to pronounce and distinct from brand names to avoid errors.

You’ll also hear INNs called “generic names” or “nonproprietary names.” They’re what doctors write on international prescriptions, what’s listed on drug formularies, and what you'll often find in the ingredients list on packaging.

In short: if you know the INN, you know the core of the medicine—regardless of what it’s called in the local pharmacy.

Why You Might Need to Search for an INN: 5 Real-Life Scenarios

Knowing the INN of a drug isn’t just for doctors or pharmacists. It can make your life a lot easier in many everyday situations. Here are five real-life examples:

1. You're traveling and need your usual medicine
You forgot your pills at home, and the local brands don’t look familiar. By knowing the INN, you can ask the pharmacist for the active ingredient instead of guessing by brand.

2. You're trying to find cheaper alternatives
Brand-name drugs can be expensive. INNs help you identify generic versions with the same effectiveness but at a lower price.

3. You're comparing medications from different countries
Sometimes doctors prescribe international brands or you’re ordering medication online. Knowing the INN helps avoid confusion and ensures you're getting the same substance.

4. You're checking for duplicate ingredients
Some cold or pain medications combine multiple ingredients. Knowing the INNs can help you avoid accidentally doubling up on the same active substance.

5. You're discussing medication with a doctor abroad
When language is a barrier, saying the INN helps ensure both you and the doctor are on the same page.

As you can see, INNs make medication safer, clearer, and more universal—no matter where you are in the world.

How to Recognize a True INN: Step-by-Step Guide

Just because a word looks like an active ingredient doesn’t always mean it’s the official INN. Here’s how to be sure you’re dealing with a real, globally recognized International Nonproprietary Name:

Step 1: Look at the format
INNs are written in lowercase (unless at the start of a sentence), and do not include ™ or ® symbols. For example, "ibuprofen" is an INN, while "Advil®" is a brand name.

Step 2: Check the language consistency
INNs are designed to be universal. A true INN should be the same across all countries—“amoxicillin” in the U.S., Europe, and Asia means the same compound.

Step 3: Verify in the WHO INN database
Go to the WHO INN database. Enter the name you suspect is an INN. If it appears in the list, it’s official.

Step 4: Confirm with reputable sources
Look up the same substance on Drugs.com or MedlinePlus. These sites usually highlight the INN and list known brand names.

Step 5: Compare with the medication’s packaging or leaflet
Check if the name listed under "active ingredient" matches the INN you've found online. Most reliable packaging includes both the brand name and INN.

Bonus Tip: Be cautious with Google results. If the site looks unofficial, doesn’t cite sources, or includes marketing buzzwords instead of medical facts, double-check using trusted databases.

Recognizing the correct INN helps you avoid confusion, buying the wrong product, or accidentally combining medications that share the same ingredient.

What If the INN Isn’t Listed?

Sometimes you won’t find the INN printed clearly on the packaging or easily visible online. Don’t worry—here’s what you can do:

1. Check the ingredients section on the packaging
Look closely at the "active ingredient" section, often in fine print. This is where the INN is usually mentioned—even if it's not highlighted on the front.

2. Search using the brand name
Use trusted websites like Drugs.com or MedlinePlus and type in the brand name. These platforms will usually show you the INN along with brand and generic alternatives.

3. Try the phrase "[Brand name] active ingredient" in Google
For example: “Panadol active ingredient” or “What is in Voltaren?” Google can help if it links you to reliable medical or regulatory sites.

4. Use medical apps or barcode scanners
Some mobile apps, like Medscape or Epocrates, allow you to search by brand name or even scan barcodes to reveal drug compositions and INNs.

5. Ask a pharmacist or healthcare provider
When you can’t confirm it yourself, the easiest and safest option is to ask a pharmacist. They’re trained to know the active ingredients behind any branded medication.

Important Reminder: Not all websites are accurate. Stick to verified databases or health authority sources, and avoid personal blogs or promotional content without citations.

Knowing how to find an INN—even when it’s not clearly labeled—can help you avoid costly or even dangerous mistakes.

INN Isn’t the Only Naming Standard: BAN, USAN, and AAN

While the INN system is the most internationally recognized, it’s not the only naming convention in use. Some countries have their own national systems for naming active pharmaceutical ingredients. Here are the most common alternatives:

1. British Approved Name (BAN)
Used in the United Kingdom, the BAN is often identical to the INN but not always. For example, adrenaline is the BAN, while epinephrine is the USAN and also recognized as the INN.
Official site: Medicines and Healthcare products Regulatory Agency (MHRA)

2. United States Adopted Name (USAN)
In the United States, drugs are named according to the USAN system. These names often align with INNs but sometimes differ in spelling or word roots. Official site: USAN Council (AMA)

3. Australian Approved Name (AAN)
Australia maintains its own approved naming system, and in most cases, AANs have been harmonized with INNs since 2016, but legacy differences may still appear. Official site: Therapeutic Goods Administration (TGA)

Why this matters: When researching medications, it helps to be aware of these systems—especially if you’re looking up drugs in a specific national context. Even if the INN isn't used, the substance is often the same.

Always cross-check the name you find with official sources, and when in doubt, rely on the INN as your baseline reference.

Common Mistakes When Searching for an INN

Even though finding an INN is relatively straightforward, people often make avoidable errors that can lead to confusion or incorrect purchases. Here are some of the most frequent mistakes to watch out for:

Mistake 1: Confusing the brand name with the INN
Just because a drug is popular doesn’t mean the name you know is its official international name. Always double-check.

Mistake 2: Assuming the same brand exists globally
Brands are regional. "Panadol" may be common in Europe and Asia, but unheard of in the U.S., where it's "Tylenol." Focus on the INN to ensure consistency.

Mistake 3: Using unofficial sources
Avoid relying on unverified blogs, forums, or marketing websites. Stick to WHO, national health agencies, or respected drug databases.

Mistake 4: Overlooking local spelling differences
Some names differ slightly by region: "sulphate" (UK) vs. "sulfate" (US). That doesn’t mean the substances are different—it’s just a language nuance.

Mistake 5: Believing that all generics are identical
While the active ingredient (INN) may be the same, formulations (excipients, absorption speed, etc.) can vary. Don’t mix up INN with identical therapeutic results.

Understanding these pitfalls will make your INN searches faster, more accurate, and much more useful.

INN vs. Generic Drug Name: What's the Difference?

In a world where people travel frequently, buy medicine online, and switch between healthcare systems, knowing a drug’s International Nonproprietary Name is no longer just useful—it’s essential. INNs give you clarity, safety, and control over your health choices.

They help you:

Avoid confusion across countries and brands
Prevent accidental overdosing or duplicating ingredients
Save money by choosing generic versions
Communicate effectively with medical professionals anywhere in the world

Remember: always use trusted sources like WHO, Drugs.com, or your national regulatory agencies. Don’t rely solely on brand names, flashy marketing, or assumptions.

Need help identifying a medication abroad? Use our free search tool on Pill in Trip to find drug names, INNs, and international equivalents. We help travelers and expats stay safe and informed.

How to Use INNs to Compare Drugs Across Countries

One of the most powerful uses of INNs is comparing medications that go by different names in different countries. Whether you're traveling, relocating, or researching alternatives, here’s how INNs help you navigate the global pharmaceutical map.

1. Search by INN, not by brand
When looking for a medication abroad, skip the brand name and search for the active ingredient (the INN). Most pharmacies can offer local equivalents once you name the INN.

2. Use international databases
Platforms like Pill in Trip, Drugs.com, and WHO INN resources allow you to see which medications in different countries contain the same INN.

3. Compare product labels
If you have access to packaging from multiple countries (or images of them online), check the “active ingredient” section. You’ll often find the same INN across all of them, even if the brand names vary.

4. Consider regional differences
Formulations, available dosages, and additional ingredients may differ from country to country. While the INN ensures the core ingredient is the same, always check the full composition for allergies or preferences.

5. Talk to a pharmacist abroad
If you’re unsure, pharmacists are your best local resource. Mention the INN, and they can point to local equivalents—even if brand names are completely unfamiliar.

By focusing on INNs, you avoid confusion, save money, and ensure you’re getting exactly what you need—wherever you are.

Final Thoughts: Why INNs Matter More Than Ever