sympathomimetic drugs

sympathomimetic drugs

agents that mimic the sympathetic nervous system, acting at alpha- or beta-adrenergic receptors within target tissues; vasoconstrictor sympathomimetics raise blood pressure by acting on alpha-adrenergic receptors, causing central vasoconstriction; beta receptor-active sympathomimetics dilate bronchi and peripheral blood vessels; beta-blockers block beta-receptor sites and promote peripheral vasoconstriction; adrenaline is a sympathomimetic drug that acts on both alpha- and beta-adrenergic receptors and is used to counter symptoms of anaphylaxis (it both raises blood pressure and dilates bronchi) Table 1
Table 1: Effects of stimulation of alpha, beta and dopamine receptors
ReceptorActionStimulating drug
Alpha-1 (α1); postsynapticVasoconstriction; positive inotropism; antidiuresisAdrenaline +
Noradrenaline +++
Alpha-2 (α2); presynapticVasodilatation; inhibition of noradrenaline releaseAdrenaline +
Noradrenaline +++
Dopamine +
Alpha-2 (α2); postsynapticConstriction of coronary arteries; promotion of salt and water excretionAdrenaline +
Noradrenaline +++
Dopamine +
Beta-1 (β1); postsynapticPositive inotropism; chronotropism; renin releaseAdrenaline ++
Noradrenaline ++
Isoprenaline ++
Dopamine +
Beta-2 (β2); presynapticNoradrenaline release accelerated; positive inotropism; chronotropismAdrenaline +
Isoprenaline +++
Beta-2 (β2); postsynapticVasodilatation; relaxation of bronchial smooth muscleAdrenaline +
Isoprenaline +++
Dopamine1; postsynapticVasodilatation; diuresisDopamine ++
Dopamine1; presynapticInhibits noradrenaline releaseDopamine +

Plus signs indicate degree of effect.

sympathomimetic drugs 

Drugs that produce an effect similar to that obtained by stimulation of the sympathetic nervous system. Some of these predominantly act on the adrenergic alpha-receptors (e.g. noradrenaline (norepinephrine)), while others act on the adrenergic beta-receptors (e.g. isoproterenol). Others have little direct effect on the adrenergic receptors but enhance the release of natural catecholamine from the sympathetic nerve terminals (e.g. amphetamine, phenylpropanolamine). Sympathomimetic drugs are used (1) in the treatment of open-angle glaucoma by decreasing aqueous humour secretion and increase the outflow through the trabecular meshwork thus reducing the intraocular pressure (e.g. adrenaline (epinephrine), apraclonidine, dipivefrine hydrochloride, brimonidine tartrate), (2) dilate the pupil without affecting accommodation (e.g. phenylephrine) and (3) constrict conjunctival blood vessels (e.g. naphazoline, tetrahydrozoline). Syn. adrenergic agonist; adrenergic stimulating agent. See alpha-adrenergic agonist; mydriatic.
References in periodicals archive ?
Intracavernosal treatment * Injection of sympathomimetic drugs (phenylephrine) 4.
Hypertension may result from use of illicit drugs, oral contraceptives, herbal supplements, nonsteroidal anti-inflammatory medications, some psychiatric medications, steroids, or sympathomimetic drugs like diet pills or decongestants (Vera & Neutze, 2010).
For instance, sympathomimetic drugs can lead to rapid increase in blood pressure, arrhythmias, myocardial infarction and heart failure,particularly in elderly patients with coronary artery disease.
Catecholamines, sympathomimetic drugs and adrenergic receptors antagonists.
Several classes of drugs including topical mydriatics anticolinergics antidepressants anticonvulsants antihistaminics sulphamate derivative adrenergics and sympathomimetic drugs have the capacity to actuate an acute attack of angle closure.
VENTRICULAR PREMATURE COMPLEXES [VPC]: VPC's are often the commonly seen arrhythmias during the peri-operative period and can be caused by cardiac and non-cardiac factors like electrolyte imbalances, hypoxia, hypercarbia, anesthetic agents, tobacco, caffeine, alcohol, sympathomimetic drugs and antidepressant drugs.
Summary: TEHRAN (FNA)- Researchers at Payam-e-Noor University of Tehran in collaboration with experts from Tabriz University of Medical Sciences found a simple synthesis method for zinc oxide (and hydroxide) and their application in modified carbon paste electrodes for determination of sympathomimetic drugs at micro-molar scales.
Administration of sympathomimetic drugs is the most effective method for maintaining blood pressure and tissue perfusion during anesthesia in horses.
Sympathomimetic drugs, including cocaine and amphetamines, are commonly associated with intracranial hemorrhage, possibly due to transient hypertension or arteritis-like vascular change.
Amphetamine (R,S-1-phenyl-2-propanamine) and methamphetamine (R,S -N-methyl-1 -phenyl-2-propanamine) are powerful stimulants that affect the central nervous system by acting as indirect sympathomimetic drugs (Kraemer & Maurer 2002).
Amphetamines are non-catecholamine indirect sympathomimetic drugs that structurally resemble noradrenaline (2).
Dental professionals should use caution when administering other sympathomimetic drugs (e.