Block 2 Pharmacology

short-acting beta-2 adrenergic agonist - examples?

Salbutamol

Salbutamol indication?

chronic/acute asthma.

exercise-induced bronchospasm.

MOA Salbutamol?

adrengeric receptor agonist, relaxes smooth muscle by binding to beta-2 receptors,

specifically in pulmonary (trachea to terminal bronchioles).

Side-effects of Salbutamol?

Arrhythmias; headache; muscle spasms; nasopharyngitis; oropharyngeal pain; palpitations; rash; tremor.

Sympathomimetic - examples?

noradrenaline

Noradrenaline indication?

acute hypotension

MOA Noradrenaline?

Peripheral vasoconstrictor - acts on alpha-adrenergic receptors.

Inotropic stimulator of the heart and dilator of coronary arteries as a result of it's activity at the beta-adrenergic receptors

Side-effects of Noradrenaline?

Acute glaucoma, anxiety, arrhythmias, confusion, headache, hypoxia, vomiting, insomnia…

beta-1 agonist - examples?

Dobutamine

Dobutamine indication?

cardiac stress testing, iontropic (contraction) support during cardiac surgery…

MOA Dobutamine?

Stimulates beta-1 receptors of the heart to increase myocardial contractility and stroke volume, resulting in increased cardiac output

Side-effects of Dobutamine?

Arrhythmias; bronchospasm; chest pain; dyspnoea (laboured breathing); eosinophilia; fever; headache; inflammation localised; ischaemic heart disease; nausea; palpitations

Non-selective beta agonist - examples?

isoprenaline

Isoprenaline indication?

Bradycardia

MOA Isoprenaline?

Agonism of beta-1 receptors = increased strength of contractility, conduction of nerve impulses, speed of relaxation, and rate in the heart.

Agonism of beta-2 adrenergic receptors = glycogenolysis in the liver, glucagon release from the pancreas, and activation of the renin-angiotensin-aldosterone system. Increase chloride ion transport across CFTR, so, passive transport of water out of alveoli.

Side-effects of Isoprenaline?

Arrhythmias, sweating, tremor, headache and flushing

beta-1 selective blocker - examples?

atenolol

Atenolol indication?

hypertension, angina, arrhythmias, migraine

MOA Atenolol?

Antagonist to Beta-1 receptors which are found in heart, kidney and adipose tissues.

Reduces HR and decreases renin secretion in kidneys.

Side-effects of Atenolol?

Abdominal discomfort; bradycardia; confusion; depression; diarrhoea; dizziness; dry eye, Raynaud’s phenomenon, erectile dysfunction.

non-selective beta blocker - examples?

Propranolol

Propranolol indication?

Thyrotoxicosis (high thyorid levels).

Hypertnsion, angina, anxiety, arrhythmias,

Phaeochromocytoma (adrenal gland tumours).

MOA Propranolol?

nonselective β-adrenergic receptor antagonist. Blocking of these receptors leads to vasoconstriction

Side-effects of Propranolol?

Abdominal discomfort; bradycardia; confusion; depression; diarrhoea; dizziness; dry eye, Raynaud’s phenomenon, erectile dysfunction.

thiazide diuretic - examples?

Bendroflumethiazide

Bendroflumethiazide indication?

oedema, hypertension, unwanted lactation

MOA Bendroflumethiazide?

inhibits active chloride reabsorption in kidneys, increases water lost to urine.

Side-effects of Bendroflumethiazide?

postural hypotension, skin reactions, alkalosis hypochloraemic; constipation; diarrhoea; dizziness; electrolyte imbalance; erectile dysfunction; fatigue; headache; hyperglycaemia; hyperuricaemia

class III antiarrhythmic example?

Amiodarone

Amiodarone indication?

arrhythmias, ventricular fibrillation

MOA Amiodarone?

blocks potassium currents that cause depolarisation of heart muscle,

increases duration of the action potential and refartory period, less excitability of cells, prevents abnormal heart rhythms.

Side-effects of Amiodarone?

hypotension, bradycardia, arrhythmias, hepatic disorders, hyperthyroidism, nausea

ACE inhibitor - examples?

Ramipril

Ramipril indication?

hypertension, symptomatic heart failure, MI

MOA Ramipril?

inhibits RAAS system by binding to and inhibiting ACE (angiotensin converting enzyme).

Side-effects of Ramipril?

Alopecia, angina pectoris, arrhythmias, chest pain, constipation, cough, depression, diarrhoea, dizziness, drowsiness; electrolyte imbalance; palpitations.

Calcium channel blocker - examples?

Amlodipine

Amlodipine indication?

angina, hypertension

MOA Amlodipine?

blocks calcium channels resulting in reduced peripheral vascular resistance in smooth muscle, so decrease in BP.

Side-effects of Amlodipine?

Abdominal pain; dizziness; drowsiness; flushing; headache; nausea; palpitations; peripheral oedema; skin reactions; tachycardia; vomiting

alpha 1 blocker - examples?

doxazosin

Doxazosin indication?

hypertension, begnin prostatic hyperplasia (noncancerous condition, prostate gland enlarges).

MOA Doxazosin?

antagonist to alpha 1 receptors, decreases systemic peripheral vasuclar resistance, reducing BP,

minimal effects on HR due to selectivity.

Side-effects of Doxazosin?

Arrhythmias; asthenia; chest pain; dizziness; drowsiness; dry mouth; dyspnoea; GI discomfort; headache; hypotension