February 12, 2016


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How does Caffeine work?

Caffeine works by stimulating the central nervous system (CNS), heart, and muscles. Caffeine also seems to improve the effectiveness of pain-relievers such as acetaminophen (Tylenol) and aspirin. Caffeine also works as a "water pill" to promote fluid loss.

Are there safety concerns?

Caffeine is safe for most adults. Caffeine can cause insomnia, nervousness and restlessness, stomach irritation, nausea and vomiting, increased heart rate and respiration, and other side effects. Caffeine can make sleep disorders in patients with acquired immunodeficiency syndrome (AIDS) worse. Larger doses might cause headache, anxiety, agitation, chest pain, and ringing in the ears. Large doses may be UNSAFE and can cause irregular heartbeats and even death.

Caffeine is probably safe in pregnant or breast-feeding women in daily amounts of less than 200 mg. This is about the amount in 1-2 cups of coffee. Consuming larger amounts during pregnancy might increase the chance of miscarriage and other potential negative effects.

Avoid excessive amounts of caffeine if:
  • You are pregnant or breast-feeding.
  • You have a heart condition.
  • You have diabetes.
  • You have anxiety.
  • You have a condition called bipolar disorder.
  • You have an eye disease called glaucoma.
  • You have high blood pressure.
  • You have osteoporosis.
  • You have a bleeding condition.

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Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

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