Medications Flashcards
ACE inhibitors (captopril/ enalapril/ pril’s)
Antihypertensive
Prevent conversion of angiotensin 1-2, results in reduced peripheral resistance and lower BP
Converted to active form in liver
Decreases aldosterone production- reduces sodium/water reabsorption
Increase plasma renin levels by negative feedback
Inhibits degradation of bradykinin leading to accumulation of bradykinin and substance P sensitising airway and producing cough
Adverse effects- hypotension, palpitations, chest pain, abdominal pain, nausea, dry mouth, taste disturbance, diarrhoea, persistent dry cough, rash, elevated potassium levels, raised liver enzymes, proteinuria, neutropenia
Rare effects- angioedema, cholestatic jaundice, hepatitis, renal impairment, anaphylaxis
Interactions- not recommended with potassium sparing diuretics, NSAIDS, give 2 hours apart from antacids (can decrease bioavailability), increased risk hypoglycaemia with diabetic agents
Nursing considerations- administer 1 hr before meals, correct volume/electrolyte depletion’s before commencing, check urine protein, don’t take with NSAIDS, not in pregnancy, infusion pump if given IV, monitor BP for 2 hours post, monitor potassium levels, monitor for neutropenia, check liver function
Angiotensin 2 receptor antagonist ( candesartan cilexetil/ losartan potassium/ tan’s)
Antihypertensive
Antagonise angiotensin 2 receptors in vascular smooth muscle and adrenal cortex
Increase renal blood flow and maintains GFR while decreasing renal vascular resistance
No inhibition of ACE so no cough
Adverse effects- back pain, myalgia, arthralgia, fly like symptoms, URTI, raised liver enzymes, decreased haemoglobin/haemocrit, UTI
Rare effects- peripheral oedema, rash, renal impairment, hepatitis, cough, insomnia
Interactions- caution with potassium soaring diuretics, may increase serum lithium levels, efficacy decreases with NSAIDS and may increase risk of renal impairment
Nursing considerations- correct volume/electrolyte depletion’s before commencing, caution with haemodialysis
Not recommended with hyperaldosteronism or heart failure
Beta blockers (atenalol, labetalol, propranolol/ lol’s)
Antihypertensive
Completely inhibit beta-adrenoceptors (SNS) reducing bodies response to adrenaline, noradrenaline and iosprenaline
Beta receptors found in heart, brain, bronchi, blood vessels, kidneys, pancreas, uterus, liver
Some have affinity for beta 1 (heart), and beta 2 (lungs), others are cardioselective (atenalol, bisoprolol, betaxolol, metoprolol)
Reduces rate of impulse through cardiac conduction system, reduces cardiac rate and force, output and myocardial O2 demand, bronchospasm, inhibition of renin release from kidneys, inhibition of catecholamine-induced lipid and carbohydrate metabolism, reduction of intraocular pressure
Adverse effects- bronchospasm, dyspnoea on exertion, cough, wheeze, bradycardia, heart block, arrhythmias, cold extremities, sleep disturbances, impotence, decreased libido, blurred vision, exacerbation of psoriasis, increased free T4, hypoglycaemia
Uncommon effects- depression, confusion, mood change, hallucination
Rare effects- thrombocytopenia, elevated liver enzymes, hepatic toxicity
Interactions- not recommended with verapamil, caution with calcium channel blockers, not recommended with class 1 arrhythmias/clonadine, decreased effect with NSAIDS, contraindicated in AV block, contraindicated in COPD/asthma/bronchospasm
Nursing responsibilities- document HR/BP, assess for contraindications like asthma
Diuretics
Increased rate of urine formation by reducing reabsorption of sodium, chloride, and water by renal tubules, either interfering with active transport mechanisms or altering tubular permeability
*carbonic anhydrase (acetazolamide)- block enzyme carbonic anhydrase increasing excretion of bicarb, sodium and water
Adverse effects- parasthesia, fatigue, headache, dizziness, anorexia, polyuria, fever, depression/excitement, abnormal liver function
Interactions- potentiate effects of anticoagulant, risk of digoxin toxicity, use with salicylates results in metabolic acidosis, decrease lithium levels, increase duration of amphetamines, effects BGL’s
- high ceiling/loop (bumetanide, etacrynic, frusemide)- limit amount of sodium reabsorbed in peritubular capillaries surrounding loop of henle, calcium and magnesium also blocked
Adverse effects- electrolyte imbalance, hypovolaemia, urinary retention, deafness, anorexia, malaise, hypotension, muscle cramps
Interactions- lithium, enhances antihypertensives, increased digoxin toxicity, reduced by NSAIDS
*thiazides (chlortalidone, hydrochlorothiazide)- interfere with sodium chloride reabsorption in distal tubules, increased excretion of potassium, magnesium and bicarb ions
Adverse effects- same as loop diuretics
- potassium sparing (spironolactone, epelerone)- does not antagonise aldosterone so doesn’t need it to be effective, reduce sodium reabsorption and potassium excretion at end of distal tubule and collecting duct, mild antihypertensive action
Adverse effects- same as loop
Nursing responsibilities- avoid foods high in potassium
*osmotic (glucose)- affect proximal tubule and descending loop of henle and strong osmotic pressure in nephron prevents water reabsorption into pertubular capillaries
Adverse effects- fever, thrombosis, flushing, precipitate Vit B deficiency, exacerbation of diabetes
Nursing responsibilities- monitor for dehydration, electrolyte imbalance, monitor hypoglycaemia, don’t administer with blood products, monitor FBC, daily wt, observe dehydration, monitor oedema, observe electrolyte imbalance
Initropics
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Direct acting vasodilator (hydralazine)
Antihypertensive
Relaxation of smooth muscle in arterioles not veins leading to reduction in peripheral resistance, increased renal blood flow, maintains cerebral blood flow but causes sodium and water retention
Hypertensive emergency in combo with B-blocker and diuretic
Adverse reaction- diarrhoea, nausea, vomiting, tachycardia, oedema, angina, headache, facial flushing
Contraindications- aortic dissection, severe tachycardia, heart failure, SLE
Nursing considerations-
Alpha-adrenoreceptor blocking agents (prazosin hydrochloride)
Antihypertensive
Catecholamine s for binding at alpha adrenoreceptors inhibiting SNS stimulation- can cause first dose effect of hypotension
Adverse affects- palpitations, postural hypotension, tachycardia, oedema, drowsiness, weakness, nervousness, blurred vision, nasal congestion, abnormal ejaculation/impotence, dry mouth, nausea, vomiting, rash
Interactions- caution in Ischaemic heart disease, angina, cerebral/coronary arteriosclerosis, marked renal impairment
Nursing considerations- assess BP and apical pulse first, take first dose at night to reduce first dose effect, avoid heavy machinery/driving in first 24hrs/increased dose, seek medical assistance if painful erection >4hrs
Central acting agents (methyldopa)
Antihypertensive
Stimulate alpha 2 adrenoreceptors causing reduction in sympathetic tone, reduced HR, peripheral vascular resistance and BP
Potassium channel activators ( nicorandil, diazoxide)
Relax smooth muscle by acting on ATP sensitive potassium channels
Antagonise action of ATP preventing closure of channel results in hyperpolarisation and relaxation of vascular smooth muscle
Atrial vasodilation and reduces afterload
Used in angina
Adverse reactions- nausea, flushing, dizziness, myalgia, palpitations,
Contraindications- hypotension, or left heart failure, caution with hepatic impairment
Antiarrhythmic agents
Class 1- (ivabradine) inhibits fast inward sodium channels responsible for phase 0 of action potential and slow membrane repolarisation- lowers HR at rest and during exercise
Bind to sodium channel when open or in refractory phase therefore greater frequency of sodium channels being open , the greater the degree of block.
Slowing conduction speed
Class 1A- later conduction velocity- (dysopyrammide, procainamide, quinidine)
Class 1B- does not alter conduction velocity, but decreases contraction (lignocaine, mexiletine)
Class 1C- decreases contractions (flecainide)
Class 2- beta blockers- inhibit effect of SNS, therefore effective for arrhythmias induced by excessive SNS stimulation
Slows conduction at atria and AV node, increasing refractory period (atenalol, metoprolol, esmolol)
Class 3- block potassium channels, prolong duration of action potential, decrease AV conduction (amiodarone hydrochloride, sotalol hydrochloride)
Class 4- calcium channel blockers- decrease action potential, decrease AV conduction, decrease contractility (verapamil, diltiazem)
Atypical antiarrhythmic ( adenosine)
Nursing responsibilities- baseline ECG, report signs drug toxicity
Glyceryl trinitrate
Anti anginal
Relaxes smooth muscle causing vasodilation.
Low dose venous dilation, high dose arterial dilation.
Pooling of blood in veins decreases blood returned to heart, this decreases CO and arterial pressure which results in decreased myocardial O2 demand, dilated coronary arteries, relaxes spasms in arteries
Comes in sublingual tablets, spray, transdermal patch
Can give three doses within 10 min
Adverse effects- headache, facial flushing, tachycardia, dizziness, restlessness, orthostatic hypotension, nausea, vomiting
Interactions- contraindicated with phosphodiesterase-5 inhibitors, increase risk of orthostatic hypotension if used with calcium channel blocker/ antihypertensive/ alcohol/ opioids/ antipsychotics, effects decreased if given with aspirin and NSAIDS, ergot alkaloids May antagonise effects, decrease effect of heparin
Nursing considerations- assess apical pulse before administering-with old if <60, ECG, correct hypovolaemia, assess electrolytes, sit down 10-20min post tablet to reduce dizziness, report manifestations of digoxin toxicity, remove patch before cardioversion/ defibrillation, GTN absorbed by PVC tube so use non-PVC, not recommended within 24hrs of MI
Calcium channel blockers
Decrease force of myocardial contraction by impeding influx of calcium ions through slow channels of cell membrane during depolarisation of cardiac and vascular smooth muscle improving myocardial O2 supply and cardiac output reducing myocardial workload.
Dilated coronary artery decreasing resistance, improving O2 supply to Ischaemic area.
Dilated peripheral arteries reducing peripheral vascular resistance and BP, decrease HR.
Negative inotropic effect.
Treats- angina, SVT, HT, cerebral spasm
Phenylalkylamine type- verapamil, benzothiazine type- diltiazem, dihydropyeidine type- nifedipine
Adverse effects- flushing, headache, abdominal pain, flatulence, gingivitis, rash, AV block,
Rare effects- elevated liver enzymes, hyperglycaemia
Interactions- grapefruit increases serum levels, caution with beta blockers-profound bradycardia, carbamazepine, cardiovascular depression if given with inhalation analgesics, increased vasodilation with nitrates
Contraindications- cardiac shock, severe bradycardia, congestive heart failure
Nursing responsibilities- don’t mix verapamil in solutions containing sodium bicarbonate, document HR/BP, observe for toxicity (nausea, weakness, decreased CO, hypotension, bradycardia, AV block)
Anticoagulants
Heparin, Vit K antagonists (warfarin), antithrombin 3 dependant anticoagulant (fondaparinux sodium(, thrombin inhibitors (bivalirudin), direct factor Xa inhibitor (apixiban)
*Heparin- combines with antithrombin 3 inactivating factor X and inhibiting conversion of prothrombin to thrombin.
Adverse effects- bleeding, thrombocytopenia, hyperkalaemia, elevated liver enzymes
Interactions- decreases effect of given with antihistamines, digoxin, nicotine. Antagonise effects of insulin, corticosteroids and ACTH.
Nursing responsibilities- check bloods, warfarin 24hrs after last SC dose and 5hrs post IV dose, administer IV alone as many interactions
*Vit K antagonist (warfarin)- Interfers with Vit K dependant synthesis of prothrombin and factors VII, IX, X in lever preventing extension of established clot or formation of clots.
Adverse effects- haemorrhage, nausea, vomiting, diarrhoea, pruritus, fatigue, headache, alopecia, cold intolerance, elevated liver enzymes
Interactions- many, increased activity with glucosamine and cranberry juice, garlic, ginko, ginseng dong, St. John’s wart
Nursing responsibilities- if needing IM injection, do in upper extremities so can observe and put pressure on it, baseline INR, stop 5 days before surgery
*Antithrombin 3 dependant anticoagulant (fondaparinux sodium)- synethetically produced selective inhibitor of factor Xa, inhibits both thrombin formation and development of thrombi
Adverse effects- bleeding, hypokalemia, insomnia, nausea, vomiting, increased liver enzymes, rash, urinary retention, UTI, oedema
Nursing responsibilities- 6 hrs post surgery, platelet counts
- direct thrombin inhibitors (bivalirudin)- synthetic analogue of hirudin (anticoagulant found one leech saliva)
Adverse effects- bleeding, fever, atrial fibrillation, back pain, headache, insomnia
Interactions- heparin stopped 30mins before starting, fragmin stopped 8 hrs before
Nursing responsibilities- monitor for MI through infusion, incompatible with diazepam, vancomycin, and others
*Direct factor Xa inhibitor (apixiban)- selective and reversible inhibitor of factor Xa not requiring antithrombin 3 for its activity, inhibits both free and clot bound factor Xa and prothrombinase activity
Adverse effects- bleeding, anaemia, nausea, vomiting, muscle spasm, peripheral oedema, pain, cough, dyspnoea, jaundice, urinary retention,
Interactions- contraindicated with HIV protease inhibitor, azole antifungal agents, other anti coags
Nursing responsibilities- stop before surgery
Antiplatelet agents
Abciximab, aspirin, cilostazol
Platelet receptors (glycoproteins IIb and IIIa) bing with fibrinogen to create platelet aggregation- antiplatelets inhibit this aggreagation
Abciximab, aspirin, cilostazol
Abciximab RMC- monoclonal antibody, glycoprotein IIb/IIIa receptor inhibitor
Adverse effects- bleeding, hypotension, dyspnoea, nausea, vomiting, antibody development, pain
Interactions- contraindicated with IV dextran
Nursing responsibilities- give 2 hours before procedure, monitor platelet count, monitor clotting times before starting, administer alone
Cardiac glycosides
Digoxin
Increase myocardial contraction.
increase the force of contractions by blocking Na/K ATP to increase Ca availability (positive inotropic), this alters the electro-physical properties of the heart by slowing HR-changes refractory period (negative chronotropism) and slow conduction velocity- decreases Automacity and resting membrane potential (negative dromotropism).
Used in chronic heart failure, atrial fibrilation, atrial flutter
Digoxin- increases force of contraction by inhibiting sodium-potassium pulp exchange in cardiac myocytes, slows and reduces conduction rate through AV node by increasing vagal activity
Contraindications- renal impairment, thyroid disorder, MI
Adverse effects- anorexia, nausea, vomiting, rash, blurred vision, dizziness, drowsiness, arrhythmias, bradycardia, bigeminy, digoxin toxicity-dysrhythmias, decreased appetite, nausea, muscle weakness, fatigue, blurred vision, seizures, confusion, Pretoxic warning signs- hypokalaemia, hypocalcaemia, hypomagnesaemia
Treatment for toxicity- ovine digoxin specific immune antigen-binding fragment
Interactions- suxamethonium, alcohol, beta 2 bronchodilators, insulin, many others. Effects enhanced with hypokalaemia, hypomagnesaemia, hypoxia
Nursing responsibilities- monitor potassium levels, serum levels in elderly, impaired renal/thyroid function, infants, electrolyte imbalance. Electrolytes and renal function monitored, avoid rapid infusion, not given 2 days prior to surgery
