Mechanisms of Action of Drugs PDF

Mechanisms of action Salbutamol -- Beta 2 agonist causes a cascade which results in an increase of CAMP levels. This results in smooth muscle relaxation which improves airflow. Ipratropium Bromide -- muscarinic antagonist which blocks the effects of acetoyline which causes dilation of the airways....

Mechanisms of action Salbutamol -- Beta 2 agonist causes a cascade which results in an increase of CAMP levels. This results in smooth muscle relaxation which improves airflow. Ipratropium Bromide -- muscarinic antagonist which blocks the effects of acetoyline which causes dilation of the airways. Prednisolone and hydrocortisone -- corticosteroid which suppresses activation of inflammatory genes and activates anti-inflammatory genes. Adrenaline 1:1000 -- stimulates alpha 1 receptors which results in vasoconstriction. Stimulates beta 2 receptors resulting in bronchodilation. Dexmethasone -- corticosteroid that reduces subglottic inflammation. Adrenaline 1:10000 -- vasoconstriction increases systemic vascular resistance and blood pressure which allows blood flow to brain and heart in cardiac arrests. Increases heart rate, contractility and electrical conduction. Bronchodilation. Atropine -- anticholinergic/ anti-muscarinic drug. Prevents parasympathetic activity through competitive binding causes increased heart rate and contractility. Amiodarone -- Anti arrhythmic drug that blocks potassium channels causing an increase in duration of action potential resulting in an increased refractory period which slows down heart rate. Aspirin -- Platelet inhibitor inactivates COX 1+2 enzymes decreasing thromboxin and prostaglandin production. Results in blood unable to clot. GTN -- converts to nitric oxide causing vasodilation resulting in preload reduction. Dilates coronary arteries causing increased blood flow to cardiac tissue. Furosemide -- potent loop diuretic stops reabsorption of sodium, potassium and chloride cause increased urination to get rid of the fluid. Diazepam and Midazolam -- a GABA enhancer, binds to receptors increasing the inhibitory effect of GABA. Reduces excitability of post-synaptic neuron causing CNS depression. Morphine -- acts on delta, kappa and mu receptors causing euphoria, sedation and analgesic effects. Potassium channels open causing an efflux of potassium and hyperpolarisation. Ondansetron -- antiemetic that binds to 5HT receptors both centrally and in GI tract. Ibuprofen -- a non-selective cox inhibitor resulting in a decreased production of prostaglandin and thromboxane. Anti-inflammatory, anti-pyretic and analgesic. Activated charcoal -- acts as an absorbent that binds to toxins in the GI tract. Prevents toxins being absorbed into bloodstream. Naloxone -- an opioid antagonist by competitively binding to opioid receptors so opioid can no longer exert effect. Nitrous oxide -- selectively inhibits NMDA receptors which prevents or decreases neurotransmitters of pain. TXA -- competitively binds to plasminogen so it can no longer bind to fibrinogen resulting in no clot breakdown. Misoprostol -- a uterotonic drug which stimulates contraction of the uterus to control the bleeding. Glucose -- increases blood sugar. Glucagon -- hormone that converts glucogen to glucose which increases blood sugar. Chlorphenamine -- inverse agonist which bins to H1 receptors on target tissue therefore inhibits histamine reactions causing gradual reduction to allergy symptoms. Benzylpenicillin -- narrow spectrum antibiotic kills very specific types of bacteria by binding to specific penicillin binding proteins inside the bacteria cell wall.