Choosing the right over-the-counter medication can be difficult, and the confusing array of claims on the front of the boxes doesn't usually help.

Many of the common phrases found on packaging (including "extra strength," "fast-acting," and "non-drowsy") may be difficult to decipher. But these can still offer some clues about what to expect.

Front-of-box claims aren't intended to provide comprehensive information. You'll want to turn the box over and look at the Drug Facts label for more details. But the tips below can help you make sense of common claims and better understand what you're buying. If you're ever in doubt about what a product does or whether it's safe, ask a pharmacist or your family doctor.

Extra or Maximum Strength

Companies use terms like these to signify that there's more of the active ingredient than in a brand's regular strength formulation. "These terms don't tell you how much more or how much you should take," says Barbara Keber, M.D., vice chair of family medicine at Northwell Health and chair at Glen Cove Hospital Northwell in Glen Cove, N.Y. For information on dosing and concentration, read the back of the package.

Timed Release

Unlike many other terms that appear on the front of OTC drug boxes, "timed release" actually has a specific meaning that's regulated by the Food and Drug Administration. That is, in part, because if the release mechanism does not work as intended, it's possible that a person would receive a dose that is unsafe or ineffective.

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A product labeled "timed release" will release small amounts of active ingredients into the body over a set period of time, rather than all at once.

Though "timed release" is defined by the FDA, similar-sounding terms such as "long acting" are not. "Long acting" may suggest that a product works for longer—and that there is a longer time between doses—compared with immediate-release products. That means you'll probably need to take fewer pills over a 24-hour period, but you'll pay for the convenience.

"Long-acting products are generally more expensive," says Barbara Young, Pharm.D., editor of Patient Medication Information for the ASHP (American Society of Health-System Pharmacists). 

Fast-Acting/Rapid Release

These are often chewable or dissolvable products that may release large amounts of the active ingredient into your body more quickly than other formulations of the same medication.

Fast-acting may be particularly helpful in situations where you want urgent relief, such as when you have hives from an allergic skin reaction, Keber says.

Non-Drowsy

Usually this means that a product does not contain ingredients that will make you feel sleepy, such as diphenhydramine. It does not mean that a medication will help you to stay alert, though some non-drowsy products may contain ingredients that can act as stimulants in some people, including pseudoephedrine or phenylephrine.

Dual Action

The term "dual action" implies that a medication has two or more ingredients with different actions. Combo meds can be a convenient way to treat multiple symptoms—such as congestion and fever—but be sure to read the active ingredients section on the Drug Facts label to avoid doubling up on ingredients by mistake, especially if you are using other meds, Keber says.

For instance, some prescription pain relievers contain acetaminophen, which also can be found in combination cough and cold medicines. Too much acetaminophen can damage the liver.

Easy Open/Senior-Friendly

Most OTC medications come in child-­resistant packaging, which can make them more difficult to open for people with arthritis and other manual dexterity issues. Look for these terms on packaging for easier-to-open containers. "But also remember to store them safely, out of reach from children and pets," Young says.

Editor's Note: This article also appeared in the July 2019 issue of Consumer Reports On Health.