A methylxanthine naturally occurring in some beverages and also used as a pharmacological agent. Caffeine's most notable pharmacological effect is as a central nervous system stimulant, increasing alertness and producing agitation. It also relaxes smooth muscle, stimulates cardiac muscle, stimulates diuresis, and appears to be useful in the treatment of some types of headache. Several cellular actions of caffeine have been observed, but it is not entirely clear how each contributes to its pharmacological profile. Among the most important are inhibition of cyclic nucleotide phosphodiesterases, antagonism of adenosine receptors, and modulation of intracellular calcium handling.
For management of fatigue, orthostatic hypotension, and for the short term treatment of apnea of prematurity in infants.
Caffeine, a naturally occurring xanthine derivative like theobromine and the bronchodilator theophylline, is used as a CNS stimulant, mild diuretic, and respiratory stimulant (in neonates with apnea of prematurity). Often combined with analgesics or with ergot alkaloids, caffeine is used to treat migraine and other headache types. Over the counter, caffeine is available to treat drowsiness or mild water-weight gain.
Mechanism of action
Caffeine stimulates medullary, vagal, vasomotor, and respiratory centers, promoting bradycardia, vasoconstriction, and increased respiratory rate. This action was previously believed to be due primarily to increased intracellular cyclic 3′,5′-adenosine monophosphate (cyclic AMP) following inhibition of phosphodiesterase, the enzyme that degrades cyclic AMP. It is now thought that xanthines such as caffeine act as antagonists at adenosine-receptors within the plasma membrane of virtually every cell. As adenosine acts as an autocoid, inhibiting the release of neurotransmitters from presynaptic sites but augmenting the actions of norepinephrine or angiotensin, antagonism of adenosine receptors promotes neurotransmitter release. This explains the stimulatory effects of caffeine. Blockade of the adenosine A1 receptor in the heart leads to the accelerated, pronounced "pounding" of the heart upon caffeine intake.
Route of administration
Caffeine and Caffeine Containing Products
Central Nervous System Agents
Central Nervous System Stimulants
Chemical Actions and Uses
Combined Inhibitors of CYP3A4 and P-glycoprotein
Cytochrome P-450 CYP1A2 Inhibitors
Cytochrome P-450 CYP1A2 Inhibitors (moderate)
Cytochrome P-450 CYP1A2 Substrates
Cytochrome P-450 CYP2C8 Substrates
Cytochrome P-450 CYP2C9 Substrates
Cytochrome P-450 CYP2D6 Substrates
Cytochrome P-450 CYP2E1 Substrates
Cytochrome P-450 CYP3A Inhibitors
Cytochrome P-450 CYP3A4 Substrates
Heterocyclic Compounds, 2-Ring
Molecular Mechanisms of Pharmacological Action
Physiological Effects of Drugs
Psychostimulants, Agents Used for Adhd and Nootropics
Drug Info/Drug Targets: DrugBank 3.0: a comprehensive resource for 'omics' research on drugs. Knox C, Law V, Jewison
T, Liu P, Ly S, Frolkis A, Pon A, Banco K, Mak C, Neveu V, Djoumbou Y, Eisner R, Guo AC, Wishart DS.
Nucleic Acids Res. 2011 Jan; 39 (Database issue):D1035-41. | PMID:21059682