Active vs Inactive Ingredients in Medication (and What That Means for You)

There are many questions surrounding prescription medication, but today we will focus on the differences in active vs inactive ingredients within medicine, and what that means for you.

When your doctor writes you a prescription, you probably ask about the name of the drug. You might even ask for clarification on why it was prescribed or how you should take it – or even what to do if you miss a dose. After all, understanding your medication is an important step in ensuring treatment success.

What you may not know is that most drugs contain a long list of non-drug inactive ingredients (often called excipients). These substances fill a variety of roles.

In this post, you’ll learn about the differences of active vs inactive ingredients, how they can change your medication, and options for limiting inactive ingredients in the event of a poor treatment response.

Medication Knowledge Saves Lives

Before we start, let’s talk about why all of this information matters. It’s important to be aware of both active (drug) and inactive (non-drug) ingredients when you take medication – and not just prescribed medication, either.

Even over-the-counter pain relievers, anti-diarrheals, and anti-nausea pills contain both active and inactive ingredients.

Being unaware about the ingredients in your medication can put you at risk. For example, you may:

• Accidentally take two OTC painkillers containing acetaminophen, inadvertently taking a much higher dose than recommended.
• If you have allergies, you might be prescribed a medication containing an allergen and take it without even realizing there is a problem – until you find yourself scrambling for an Epipen.

Medication knowledge saves lives. While there is so much your pharmacist can do to help keep you safe, like updating your chart and pre-checking medication against your profile, you can and should play an active role in knowing the ingredients in the drugs you take.

That knowledge could very well save YOUR life, too.

Defining Active vs Inactive Ingredients

What’s the difference with an active vs inactive ingredient, anyway?

— Active Ingredients

Active ingredients make up the core therapeutic portion of your medication, and provide some kind of distinct benefit.

For example, Tylenol contains the active ingredient acetaminophen, a relatively safe painkiller (when taken correctly).

— Inactive Ingredients

Inactive ingredients are substances that don’t have any direct therapeutic benefit, but that doesn’t mean they aren’t important. They may be used as:

• Binders
• Fillers
• Buffers
• Flavorings
• Stabilizers
• Coatings
• Even to make a drug break down at a specific rate after you take it

In the previous example, Tylenol, most branded formulas contain the inactive ingredient cornstarch as a binder. Although it doesn’t have any therapeutic benefit, cornstarch keeps the pill together and stops it from breaking down – and that both preserves the drug while also making it easier to take.

There is a difference between active vs inactive ingredients, but for a reason.

Can Inactive Ingredients Be Harmful?

In a word – yes, but with a few exceptions. As with most concerns in medicine, there is a lot of grey area for what patients and care teams consider harmful. Outside of allergies and sensitivities, most doctors prescribe medication because they believe the risks are lower than the benefits associated with treatment.

Never assume that just because a drug contains inactive ingredients, it is automatically harmful; you may inadvertently put yourself at risk. Your pharmacist is a great resource if you have questions about your medication!

— Allergies

To address the issue of harm from inactive ingredients directly, allergies and sensitivities are the biggest concern. Although it is rare, some patients react to these inert substances (like wheat or corn starch), experiencing troubling symptoms or an exacerbation of symptoms.

This is very common for patients with Celiac’s Disease (CD) because many medications use wheat-based fillers.

So, what should you do if you have allergies?

If you have specific allergies, it’s essential to contact your compounding pharmacy to see what medications they can compound for you. This means they can remove the ingredients that cause allergies.

For example, if you have a gluten allergy, your compounding pharmacist can create gluten-free medication for you.

Other patients aren’t allergic, but fail to properly absorb drugs containing certain fillers (like corn starch). While not technically dangerous, this experience can lead to poor treatment outcomes.

What to Know About Inactive Ingredients

No two active ingredients are exactly the same. Some have a higher risk profile than others. These common “problem products” include:

• Alcohol, which is a known carcinogen.

In most cases, alcohol is utilized in topical medications, but it may be used to break down, stabilize, or thin certain syrups and oral liquids.

• Aspartame, an artificial sweetener.

Aspartame is mostly used to enhance the flavor of a drug, but has been correlated with neurological issues, and potentially, certain cancers. While the evidence isn’t conclusive, most pharmacists agree it shouldn’t be used in drugs for children under 18.

• Saccharine, another artificial sweetener.

Like aspartame, it has been linked to certain neurological issues and potentially, certain cancers. Compared to aspartame, however, saccharine appears to be the safer choice.

List of Common Inactive Ingredients

There are many, many other inactive ingredients used in drugs on the commercial market. In fact, the list is far too long to outline on a single page!

Here are a few examples of the most commonly-used substances:

• Acacia
• Acesulfame potassium
• Banana
• Barium sulfate
• Benzalkonium chloride
• Dyes, like D&C Green No. 5
• Potato starch
• Polyethylene glycol
• Sodium carbonate
• Sodium chloride
• Tapioca starch
• Vanilla flavoring
• Wheat starch

It is important for you to know that not all of these ingredients are harmful or risky for every patient. The golden rule is that you should always inform your pharmacist of any reactions, allergies, or concerns before you take medication.

Should I Stop Taking Medication That Contains Inactive Ingredients?

Now that you know active vs inactive ingredients, should you stop taking medications with inactive substances?

Not necessarily.

When treatment fails, or when patients avoid a drug because it makes them develop allergy symptoms, there is a heightened risk for a worsening of symptoms.

Simply stopping your medication isn’t always the best option, but neither is continuing to take a drug containing active OR inactive ingredients that make you feel unwell. It’s far more important to be aware of the drugs you take and what they contain.

But what if you know you have an allergy or a sensitivity? You have options!

— What Are My Options?

Compounding pharmacies can help you avoid problematic inactive ingredients by reformulating your medication with alternatives – or without the inactives altogether.

Even when the action provided by the inactive ingredient is mandatory (e.g., when a drug must contain a stabilizer), there are so many alternatives out there that it becomes remarkably easy for the pharmacy to choose an alternative.

Perhaps more importantly, it also means there’s no reason for you to suffer through difficult symptoms or poor treatment outcomes correlated with your response to inactives.

Understanding active vs inactive ingredients in medicine is essential to keeping yourself healthy.

Have questions about your medications? Contact your local pharmacy and get answers. Taking an active role in your treatment plan can help keep you safe.

Common Questions About Medication