Dopamine, sold under the brand name Intropin among others, is a medication most commonly used in the treatment of very low blood pressure, a slow heart rate that is causing symptoms, and, if epinephrine is not available, cardiac arrest.[3] In newborn babies it continues to be the preferred treatment for very low blood pressure.[4] In children epinephrine or norepinephrine is generally preferred while in adults norepinephrine is generally preferred for very low blood pressure.[5][6] It is given intravenously or intraosseously as a continuous infusion.[3] Effects typically begin within five minutes.[3] Doses are then increased to effect.[3]
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Trade names | Intropin, Dopastat, Revimine, others |
Other names | 2-(3,4-Dihydroxyphenyl)ethylamine; 3,4-Dihydroxyphenethylamine; 3-hydroxytyramine; DA; Intropin; Revivan; Oxytyramine; Prolactin inhibiting factor; Prolactin inhibiting hormone |
AHFS/Drugs.com | Monograph |
Routes of administration | Intravenous injection |
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Physiological data | |
Source tissues | Substantia nigra; ventral tegmental area; many others |
Target tissues | System-wide |
Receptors | D1, D2, D3, D4, D5, TAAR1[2] |
Agonists | Direct: apomorphine, bromocriptine Indirect: cocaine, substituted amphetamine, cathinone, bupropion |
Antagonists | Neuroleptics, metoclopramide, domperidone |
Metabolism | MAO, COMT,[2] ALDH, DBH, MAO-A, MAO-B, COMT |
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Metabolism | MAO, COMT,[2] ALDH, DBH, MAO-A, MAO-B, COMT |
Excretion | Kidney |
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Chemical and physical data | |
Formula | C8H11NO2 |
Molar mass | 153.181 g·mol−1 |
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Density | 1.26 g/cm3 |
Melting point | 128 °C (262 °F) |
Boiling point | decomposes |
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Common side effects include worsening kidney function, an irregular heartbeat, chest pain, vomiting, headache, or anxiety.[3] If it enters into the soft tissue around the vein local tissue death may occur.[3] The medication phentolamine can be given to try to decrease this risk.[3] It is unclear if dopamine is safe to use during pregnancy or breastfeeding.[3] At low doses dopamine mainly triggers dopamine receptors and β1-adrenergic receptors while at high doses it works via α-adrenergic receptors.[3]
Dopamine was first synthesized in a laboratory in 1910 by George Barger and James Ewens in England.[7] It is on the World Health Organization's List of Essential Medicines.[8] In human physiology dopamine is a neurotransmitter as well as a hormone.[9]
In newborn babies it continues to be the preferred treatment for very low blood pressure.[4] In children epinephrine or norepinephrine is generally preferred while in adults norepinephrine is generally preferred for very low blood pressure.[5][6]
In those with low blood volume or septic shock, this should be corrected with intravenous fluids before dopamine is considered.[3]
Low-dosage dopamine has been routinely used for the treatment and prevention of acute kidney injury. However, since 1999 a number of reviews have concluded that doses at such low levels are not effective and may sometimes be harmful.[10][11]
Since the half-life of dopamine in plasma is short—approximately one minute in adults, two minutes in newborn babies and up to five minutes in preterm babies—it is usually given as a continuous intravenous drip rather than a single injection.[12]
A fluorinated form of L-DOPA known as fluorodopa is available for use in positron emission tomography to assess the function of the nigrostriatal pathway.[13]
Dopamine should generally not be given to people who have a pheochromocytoma or uncorrected very fast heart rate.[3]
The LD50, or dose which is expected to prove lethal in 50% of the population, has been found to be: 59 mg/kg (mouse; administered intravenously); 950 mg/kg (mouse; administered intraperitoneally); 163 mg/kg (rat; administered intraperitoneally); 79 mg/kg (dog; administered intravenously).[14]
If extravasation occurs local tissue death may result.[3] The medication phentolamine can be injected at the site to try to decrease the risk of tissue death.[3]
Its effects, depending on dosage, include an increase in sodium excretion by the kidneys, an increase in urine output, an increase in heart rate, and an increase in blood pressure.[12] At low doses it acts through the sympathetic nervous system to increase heart muscle contraction force and heart rate, thereby increasing cardiac output and blood pressure.[15] Higher doses also cause vasoconstriction that further increases blood pressure.[15][16]
While some effects result from stimulation of dopamine receptors, the prominent cardiovascular effects result from dopamine acting at α1, β1, and β2 adrenergic receptors.[17][18]
In March 2024, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) adopted a positive opinion, recommending the granting of a pediatric use marketing authorization (PUMA) for the medicinal product Neoatricon, intended for treatment of hypotension in neonates, infants and children under 18 years of age.[19] The applicant for this medicinal product is BrePco Biopharma Limited.[19]
According to Hornykiewicz,6 dopamine was first synthesized by George Barger and James Ewens in 1910 at the Wellcome labs in London, England.
Dopamine binds to alpha-1 and beta-1 adrenergic receptors. Mediated through myocardial beta-1 adrenergic receptors, dopamine increase heart rate and force, thereby increasing cardiac output. Alpha-1 adrenergic receptor stimulation on vascular smooth muscle, leads to vasoconstriction and results in an increase in systemic vascular resistance
Dopamine binds to beta-1, beta-2, alpha-1 and dopaminergic receptors.