alphaagonists
alpha adrenergic agonists
see also:
- excessive systemic dosing may cause hypertensive crisis which may be fatal, and attempts to treat such alpha agonist crises with beta adrenergic blockers or calcium channel blockers may cause acute pulmonary oedema (APO) and thus these agents are contra-indicated!!
introduction
- generally refers to agonists of the alpha-1 adrenergic receptor
- these agents cause vasoconstriction, tachycardia and generally increase cardiac output and blood pressure
- thus they are commonly used as:
- vasopressors such as in Rx of anaphylaxis
- local vasoconstriction such as when used with local anaesthetic agents (eg. Co-Phenylcaine Forte Spray) or as vasoconstrictor nasal drops for the common cold
- nasal vasoconstrictors for rhinitis such as oral pseudoephedrine
- inhaled vasoconstriction such as adrenaline / epinephrine nebulisers for croup
- excess doses may cause hypertension, acute pulmonary oedema (APO), acute coronary syndromes, cardiac arrhythmias, or gut and limb ischaemia with resultant lactic acidosis, particularly in susceptible patients such as those with hypertension, ischaemic heart disease (IHD) or peripheral vascular disease (PVD or PAD)
- examples include:
- pseudoephedrine (Sudafed)
alphaagonists.txt · Last modified: 2019/07/15 07:33 by 127.0.0.1