Caffeine is an effective tool to help you stay awake and mentally alert when you’re feeling fatigued.
When Vivarin is used as directed, it’s a safe way to stay alert.

If you use caffeine excessively, you might recognize some of these caffeine side effects. Click each icon to learn more:
Nervousness
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Irritability
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Rapid Heartbeat
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Dizziness
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Upset Stomach
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Diarrhea
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Sleep Issues
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Nervousness/Anxiety
As a stimulant, caffeine can cause an increased heart rate and elevated blood pressure, which may contribute to nervousness. Having too much caffeine may leave you feeling anxious and moody and can trigger physical reactions such as nausea and headaches. In addition, this intensified alertness can serve as a double-edged sword, increasing anxiety by making you more aware of all the potential negative outcomes in a situation
Back to TopIrritability/Restlessness
Irritability is an unpleasant feeling of being overly sensitive to stimulation and easily annoyed. The caffeine found in coffee can produce a heightened sense of perception by stimulating the brain, or nervous system. This effect makes a person more aware of mild annoyances, thereby increasing irritability. It also may lead to body tremors or overall jitteriness.
Back to TopRapid Heartbeat
Caffeine is absorbed from your stomach into your bloodstream. As a result, caffeine can raise your blood pressure for a short period of time, causing a rapid or irregular heartbeat and breathing trouble. If you have irregular heart rhythms, caffeine may make your heart work even harder.
Back to TopDizziness
Dizziness, often described as light-headedness, giddiness or unsteadiness, can result from motion, injury, medications or illness. Caffeine, like tobacco and other stimulants, actually reduces blood flow to the brain, which is why you may feel dizzy if you ingest too much.
Back to TopUpset Stomach/Heartburn
Caffeine raises the amount of acid in your stomach and may cause heartburn or upset stomach by relaxing the floodgates of the lower esophageal sphincter, allowing stomach acid to regurgitate back into your system.
Back to TopDiarrhea and Frequent Urination
The caffeine you consume is instrumental in contributing to peristalsis, which is the process that moves food through your digestive system. Caffeine stimulates the muscles in your colon to alternately contract and then relax, resulting in an increased need to move your bowels.
In addition, caffeine is a diuretic, prompting your body to get rid of excess fluids. Specifically, caffeine is not stored in your body but is processed in the liver and exits through your urine.
Back to TopSleep Issues
Caffeine helps you stay alert, so having too much of it before bedtime can interfere with your sleep patterns. As a result, it may be difficult to fall asleep, stay asleep or get a good night’s sleep.
Back to TopAvoiding Caffeine Side Effects
It’s easy to avoid the side effects of too much caffeine – use it only occasionally when you need to boost your energy. Read the label of any caffeine product that you use, including Vivarin, so you know exactly how much to take.
For example, Vivarin is safe for adults and children over 12 and can be taken not more often than every three to four hours.
Just so you know: Your mileage may vary with any caffeine product, depending on your age, health and body mass.
Whether you need to boost your mental power for a study session or want to be more productive at work, Vivarin can help you stay alert when you need to and it’s safe, convenient and only 200 mg of caffeine.