Caffeine

Mechanism-of-action class: Enzyme Inhibitors.

• Use helps restore mental alertness or wakefulness when experiencing fatigue or drowsiness

Directions adults and children 12 years and over: take 1 tablet not more often than every 3 to 4 hours children under 12 years: do not use

For occasional use only Caffeine warning: The recommended dose of this product contains about as much caffeine as a cup of coffee. Limit the use of caffeine-containing medications, foods, or beverages while taking this product because too much caffeine may cause nervousness, irritability, sleeplessness, and, occasionally, rapid heart beat. Do not use for children under 12 years of age as a substitute for sleep Stop use and ask a doctor if fatigue or drowsiness persists or continues to recur. If pregnant or breast-feeding, ask a health professional before use. Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center right away.

• Dec 28, 1981ANDAANDA086996Sandoz
• Oct 4, 1983ANDAANDA086557Cosette
• Nov 9, 1984ANDAANDA088616Actavis Labs Ut Inc
• Mar 17, 1986ANDAANDA089007Dr Reddys Labs Sa
• Jan 21, 1987ANDAANDA089175Mikart
• Jul 30, 1992NDANDA020232Actavis Labs Ut Inc
• Jan 14, 1998NDANDA020802Haleon Us Holdings
• Sep 21, 1999NDANDA020793Hikma

1. 1Drug Ineffective7,09115%
2. 2Product Use In Unapproved Indication5,03011%
3. 3Headache4,5469.7%
4. 4Nausea4,0038.6%
5. 5Fatigue3,9438.4%
6. 6Pain3,8878.3%
7. 7Drug Effective For Unapproved Indication3,3447.2%
8. 8Off Label Use2,8606.1%
9. 9Diarrhoea2,7856.0%
10. 10Vomiting2,7215.8%
11. 11Dyspnoea2,7035.8%
12. 12Dizziness2,6335.6%
13. 13Arthralgia2,6065.6%
14. 14Abdominal Discomfort2,4805.3%
15. 15Rash2,3295.0%

Recent PubMed references pinned to Caffeine as a MeSH major topic. Citations link to pubmed.ncbi.nlm.nih.gov.

• Effects of Taurine-, Caffeine-, and Phosphatidylserine-Containing Supplementation Protocols on Physical and Cognitive Performance in Professional Male Football Players.
  Nutrients · 2026 · Mizera K, Mizgała-Izworska E, Mizera J, et al.
  PMID 42280328DOI 10.3390/nu18111684
• Neurovascular-immune mediator dynamics in migraine: State-dependent effects of caffeine.
  Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology · 2026 · Khasawneh RR, Almahasneh FA, Abu-El-Rub E, et al.
  PMID 42257903DOI 10.1007/s10072-026-09161-7
• Effects of caffeine gum on same-day and subsequent neuromuscular performance under a standardized resistance-priming condition in male basketball players.
  Journal of the International Society of Sports Nutrition · 2026 · Wang J, Li B, Huang Y, et al.
  PMID 42247558DOI 10.1080/15502783.2026.2682313
• The Effect of CYP1A2 Gene Polymorphisms on Caffeine Pharmacokinetics and Exercise Performance in Male Recreational Athletes.
  European journal of sport science · 2026 · Masters C, Ali A, Badenhorst C, et al.
  PMID 42230302DOI 10.1002/ejsc.70203
• Hepatic CYP1A2 Activity in Adolescents with and without Obesity Assessed by the Urinary Paraxanthine-to-Caffeine Metabolic Ratio: A Pharmacokinetic Study.
  Journal of clinical pharmacology · 2026 · Gade C, Ullah S, Dalhoff K, et al.
  PMID 42212530DOI 10.1002/jcph.70219
• Differential Time-of-Day Effects of Caffeine Capsule and Mouth Rinse on Physical Performance and Volleyball-Specific Skills in Adolescent Male Volleyball Players.
  Nutrients · 2026 · Amor SB, Dhahbi W, Souaifi M, et al.
  PMID 42196973DOI 10.3390/nu18101514
• Effects of Caffeine Supplementation on Cognitive Function and Neuromuscular Performance Across Menstrual Cycle Phases in Eumenorrheic Female Athletes: A Randomized, Double-Blind Placebo-Controlled Pilot Trial.
  Nutrients · 2026 · Ben Hsen I, Hamdi S, Ceylan Hİ, et al.
  PMID 42196972DOI 10.3390/nu18101512
• The Caffeinated Brain Part 1: The Effects of Caffeine on Event-Related Potentials (ERPs)-A Systematic and Mechanistic Review.
  Nutrients · 2026 · Chmiel J, Malinowska A, Kurpas D, et al.
  PMID 42196950DOI 10.3390/nu18101489

The 10 most recently updated of 1,182 ClinicalTrials.gov registrations naming Caffeine as an intervention. Registration is not evidence of efficacy or safety — reference crosswalk only.

• Sleep Hygiene During Ramadan
  Completed · Interventional · 64 enrolled · The Higher Institute of Sport and Physical Education of Sfax
  NCT07639229updated 2026-06-12
• Efficacy of Cognitive Behavioral Therapy for Insomnia to Treat Insomnia Symptoms in Individuals With Multiple Sclerosis
  Recruiting · Phase 2 · Interventional · 70 enrolled · University of Kansas Medical Center
  NCT06428006updated 2026-06-12
• Evaluating the Impact of Energy Drink Formulas on Alertness for an Extended Period
  Active not recruiting · Interventional · 48 enrolled · PepsiCo Global R&D
  NCT07400614updated 2026-06-12
• Post-Concussion Sleep and Brain-heart Functions
  Not yet recruiting · Interventional · 70 enrolled · University of Ottawa
  NCT07636408updated 2026-06-11
• Effects of Caffeine on Chess Performance and Cognitive Function in Professional Chess Players
  Not yet recruiting · Interventional · 12 enrolled · St. Louis University
  NCT07641335updated 2026-06-11
• Thrive With Type 1 Diabetes 2026
  Recruiting · Interventional · 48 enrolled · Emory University
  NCT07522866updated 2026-06-11
• Randomized Evaluation of Voucher Interventions for Value and Effectiveness (REVIVE) in Philippines
  Recruiting · Interventional · 5,320 enrolled · International Food Policy Research Institute
  NCT07640594updated 2026-06-10
• Sensory and Behavioral Sleep Training
  Recruiting · Interventional · 54 enrolled · Atlas University
  NCT07638605updated 2026-06-10
• Endoscopic Injection of Autologous Fat-Derived Cells (SVF) for Adults With Refractory Gastroesophageal Reflux Disease (GERD). (The GERD-REVIVE Pilot Study)
  Not yet recruiting · Interventional · 15 enrolled · Fondazione Policlinico Universitario Agostino Gemelli IRCCS
  NCT07638423updated 2026-06-10
• Efficacy of a Self-advocacy Serious Game Intervention
  Active not recruiting · Phase 2 · Interventional · 336 enrolled · University of Pittsburgh
  NCT04813276updated 2026-06-10

CPIC-curated drug–gene pairs for Caffeine. Levels describe the strength of curated evidence and guideline status — never a recommendation to test or to adjust therapy.

• ADORA2ACPIC D (provisional)ClinPGx 3

Frequently asked questions

How does Caffeine work?

Mechanism-of-action class: Enzyme Inhibitors.

What is Caffeine used for?

According to FDA labeling, Caffeine carries indications including: Use helps restore mental alertness or wakefulness when experiencing fatigue or drowsiness. This is a reference summary of labeled uses, not medical advice or a treatment recommendation.

What class of drug is Caffeine?

Caffeine is classified as Other dermatologicals, Xanthine derivatives, Central Nervous System Stimulant, Methylxanthine, Enzyme Inhibitors, Bronchodilation, Cardiovascular Activity Alteration, Central Nervous System Stimulation, Decreased Collecting Duct Water Permeability, Increased Central Nervous System Organized Electrical Activity.

What are the brand names for Caffeine?

Caffeine is marketed under brand names including Anacin, Anacin Advanced Headache Formula, Arthriten Inflammatory Pain, Ascomp, BC Arthritis, BC Original Formula, Backaid IPF, Backprin.