What Are Caffeine Pills—and Are They Safe?

Caffeine pills are easily accessible, portable, and cheap. You can buy pills such as No Doz, Revive, Vivarin, and many others online or at your local pharmacy, and they're tiny enough to tuck away in any backpack. So it's not surprising that college students rely on them to overcome morning fatigue, stave off an afternoon slump, or pull all-nighters.

Though there's no denying the burst of energy you get from caffeine pills, the question is, are they healthy? Here's what you need to know.

What Are Caffeine Pills?

As many people know, caffeine is a stimulant that acts on the central nervous system—nerves, brain, and spinal cord—to make you feel more awake and alert.

Caffeine pills can be made of natural or synthetic caffeine. Some products may also contain inactive ingredients, such as fillers, coloring agents, emulsifiers, and other additives, said Rachel Link, RD, a nutritionist based in New York City.

Cynthia Sass, RD, Health nutrition editor, said while every type of pill is made differently, most have between 100 and 200 milligrams of caffeine. For comparison, that's:

• less than a 20-ounce cup of Starbucks Dark Roast brewed coffee (591 milligrams)
• more than a 20-ounce bottle of Coca-Cola (57 milligrams)
• on par with a 16-ounce can of Monster Energy (160 milligrams)

What's the Difference Between Caffeine Pills and Coffee?

There are a few significant differences between caffeine pills and coffee. Caffeine pills are "more accessible or portable than coffee, and some people don't like the taste of coffee or tea," Sass said.

Because coffee can be so bitter, people often add creamer and sweetener. Taking a pill avoids the sugar shock and taste of coffee altogether. It's also calorie-free, which may be the appeal, Sass reasoned.

Sometimes "coffee can also irritate the digestive tract" and "trigger heartburn," Link said, which is why some people are drawn to using caffeine pills.

Additionally, caffeine pills hit you faster since you take a caffeine supplement all at once, said Julie Upton, RD, co-founder of Appetite for Health in the San Francisco Bay area. And the caffeine crash can hit you harder since the pills "contain a more concentrated dose of caffeine than other drinks," Link said.

Many caffeinated beverages contain beneficial compounds in addition to caffeine. For example, L-theanine, which is found in tea, helps to prevent adverse side effects of caffeine, Link said. Because caffeine pills lack these compounds, they increase a person's risk of suffering from negative side effects, Link added.

How Much Caffeine Is Too Much?

According to the Substance Abuse and Mental Health Services Administration (SAMHSA), when energy drinks became very popular in 2011, emergency departments began seeing patients who had consumed too much. As a result, tens of thousands of people were seen for caffeine-related complications.

Any amount of caffeine can be too much if it upsets your stomach, makes your heart race, causes you to lose sleep, or stokes other unpleasant side effects. It depends on how sensitive you are to caffeine's effects, and how quickly you break down the substance.

For a healthy adult, up to 400 milligrams of caffeine, a day is considered a safe amount, according to the FDA. This is the same as about four or five cups of coffee. Consuming higher doses can be risky for people who are pregnant or nursing; children and adolescents; and people with a chronic illness or disease, since certain conditions and medications can make people more sensitive and vulnerable to the effects of caffeine, the FDA additionally pointed out.

Caffeine can be toxic if you take in too much too quickly. Serious effects, including seizures, have been linked to rapid consumption of about 1,200 milligrams, the FDA reported.

"The dangers are especially concerning if caffeine is taken in higher doses, combined with other stimulants, or under certain conditions, like existing high blood pressure," Sass said. The National Library of Medicine (NLM) noted that intaking 10 grams or more of caffeine in one sitting could be fatal.

Furthermore, the FDA had also given several manufacturers warnings over pure and highly concentrated caffeine in liquid or powder forms after noting just two deaths caused by that type of caffeine.

What Are Caffeine Side Effects?

High doses of caffeine can cause issues such as "agitation, severe anxiety, elevated blood pressure, and palpitation," as indicated by a February 2022 article in JAMA. You should check with your healthcare provider immediately if any of these symptoms occur or if you show signs of overdose. Symptoms of overdose include irritability, nervousness, rapid heartbeat, and trouble sleeping. Other side effects, like a rash or dry skin, can occur but do not require medical attention.

What if it's just a case of caffeine jitters? For minor caffeine ingestion, supportive measures—like drinking water and taking a walk—can help, Link suggested. More severe cases may require intravenous hydration or medications to treat irregular heart rhythms, for example. In life-threatening situations, dialysis may be the best option.

So, Are Caffeine Pills Safe?

Even though consuming up to 400 milligrams of caffeine a day is generally considered safe, it doesn't mean it's a healthy habit. It is possible to develop a dependence on caffeine pills, said Ryan D. Andrews, RD, author of A Guide to Plant-Based Eating.

Sass and Link didn't recommend them because the risks outweigh the benefits, they said. It's much easier to consume too much caffeine, and caffeine supplements don't provide the same beneficial compounds.

If you decide you want to try caffeine pills anyway, speak with your healthcare provider first about whether they are the right way for you to get an energy boost.