How to read over the counter (OTC) drug labels

What claims such as ‘long acting’ and ‘24 hour’ actually mean

Published: April 2014

You’ll find about 15 versions of Advil (such as “PM”) and 20 kinds of Tylenol (including those made for kids). And that’s not counting the various types of generic pills—tablets, caplets, and liquid gels— and sizes of containers.

Deciding what to buy can be especially overwhelming when you’re miserable with allergies or a springtime cold. So which one do you choose?

With the help of our medical experts and researchers at Best Buy Drugs, who evaluate medications for safety, price, and effectiveness, we have some advice for you. Keep reading to find out what some common over-the-counter drug-label claims really mean, and when you should take what.


Examples: Non-Drowsy Claritin Indoor & Outdoor Allergies, Allegra Allergy Original Strength Non-Drowsy, Alavert Non-Drowsy

What it means: “Non-drowsy” is code for antihistamines and other medications that don’t make you sleepy. They’re a good choice for allergy relief during daytime hours. But the non-drowsy claim doesn’t necessarily mean that the drugs will help you stay alert, though some might contain stimulating ingredients.

Our advice: Read medication ingredient labels carefully. On non-drowsy formulas, look for stimulants such as the decongestant pseudoephedrine (like Claritin D, above) and caffeine, which could keep you awake at night.


Examples: Advil PM, Motrin PM

What it means: “PM” formulas usually contain one of two active ingredients: diphenhydramine (found in Benadryl) or doxylamine, which can make you sleepy. Both are antihistamines that affect the central nervous system.

Our advice: Many of these drugs contain pain relievers such as acetaminophen or ibuprofen. But if you just want a pill to help you sleep, stick with single-ingredient products containing diphenhydramine or doxylamine, such as Sominex or Unisom. If you take blood-pressure meds, avoid those drugs because the combo may cause excessively low blood pressure. Skip drinking alcohol with them, and use caution if you drive the next day.

24 hours

Examples: Allegra 24 Hour, Claritin 24 Hour, Zyrtec 24 Hour

What it means: We used to see drugs with labels that said “all day,” but now specific time claims are more common. That’s good news, because “all day” could refer to just the part of the day when you’re awake or to a full 24-hour period. The 24-hour label makes that clear. These are extended-release drugs; you take one dose per day and it keeps working over the course of an entire day and night.

Our advice: Watch out for nonspecific language that suggests 24 hours. Case in point: Aleve still says “All Day Strong” on its packaging, yet its directions say to take one tablet every 8 to 12 hours while symptoms last and not to exceed three tablets in a 24-hour period.


Examples: Robitussin Lingering Cold Long-Acting CoughGels, Sudafed 12 Hour Long-Acting Nasal Decongestant

What it means: That depends. Some drugs say “24 hour” or “12 hour.” You can buy both versions of Sudafed, for example, and each comes with a “long-acting” claim. All it means is that their active ingredients are released during a certain amount of time.

Our advice: Read instructions, even for products that claim to last a certain number of hours. For example, there might be a max number of pills you should take in a 24-hour period.

‘Extra ’ vs. ‘Ultra ’ strength

These formulas contain more of the active ingredient than the regular type (ditto for “maximum” strength), but there’s no set definition of those terms. So always read dosage instructions.

Editor's Note:

This article also appeared in the May 2014 issue of ShopSmart magazine. This article and related materials are made possible by a grant from the state Attorney General Consumer and Prescriber Education Grant Program, which is funded by the multistate settlement of consumer-fraud claims regarding the marketing of the prescription drug Neurontin (gabapentin).

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