Adrenergic drugs with its drug classification and mecahnism of action

definition, function, drug classification, mechanism, pharmacokinetics, ADRs,

1. ADRENERGIC DRUGS ANJALI RANA (M.PHARM-PHARMACOLOGY)

2. ADRENERGIC DRUGS ( SYMPATHOMIMETIC DRUGS)- “ are the drugs which produce an effect similar to the stimulation of post ganglionic nerves sympathetic or adrenergic nerves.” Adrenergic nervous system- it is a group of organs & nerves in which adrenaline or/and noradrenaline are released as neurotransmitter . Adrenergic receptors- a) alpha ( α -1, α -2) b) beta ( β -1, β -2, , β -3) c) dopamine (D1 &D2). Function of Adrenaline neurotransmitter- it is responsible for body sympathetic response, the “Fight, Flight & Fear” state which a)dilate pupil b) increase heart rate c) increase respiration (dilate bronchi) d) diverts blood flow to the muscle e) release stored energy

3. CLASSIFICATION OF ADRENERGIC DRUGS DIRECTLY ACTING a) catecholamines :- A drenaline, N oradrenaline , D opamine, b)non- catecholamines :- D obutamine I soprenaline INDIRECTLY ACTING:- M odafinil A mfetamines T yramine MIXED ACTING :- M ephentermine E phedrine D opamine

4. MECHANISM OF ACTION ADRENERGIC DRUGS Noradrenaline acts on α -receptors where as adrenaline stimulate both α & β receptors. Noradrenaline cause increased contractility & recxeptor causing vasoconstriction in Blood vessels, B.P. is increase, HR increase & improve coronary blood flow. Noradrenaline is mainly used for raising blood pressure in case of shock.

5. #PHARMACOLOGICAL ACTION OF ADRENERGIC DRUGS 1. Action on Heart- act on β -receptors & produce increase heart rate. 2. Action on Blood Vessls - constricts the blood vessels of skin & mucous. 3. Action on blood pressure- increase blood pressure. 4. Action on Eyes- Adrenaline produces Mydriasis . 5.Action on skeletal muscles- it improves neuromuscular transmission & relieves fatigue of skeletal muscles. 6. Action on respiration- it has no bronchodilator effect. 7. Action on smooth muscles- it relaxes the pain muscles of intestines. 8.Action on CNS- increase tremors, restlessness & palpitation. #PHARMACOKINETICS –a)onset of action- 1 to 2min. b)it can crosses placenta c) metabolized in liver d)excreted through urine.

6. #SIDE EFFECTS:- 1) Headache 2) Insomnia 3 restlessness 4) anxiety 5) decrease urine output 6) hypertension 7) Nausea & vomiting.