Medications Flashcards
ABCIXIMAB
Antiplatelet agent – monoclonal Ab against platelet glycoprotein IIb/IIIa receptor (involved in Pt aggregation).
Use: Px of ischaemic complications of PCI and Px of MI in unstable angina unresponsive to conventional Rx awaiting PCI.
CI: active internal bleeding. CVA w/in 2 years. Intracranial neoplasm, aneurysm or AVM. Major surgery, intracranial/intraspinal surgery or trauma w/in 2 months. Hypertensive retinopathy, vasculitis, ↓Pt, haemorrhagic diathesis, severe BP. L (if severe)/R (if requiring haemodialysis)/B.
Caution: drugs that increase bleeding risk, L/R/LP/E.
SE: bleeding* /↓Pt*, N&V, ↓BP, ↓HR, pain (chest, back or pleuritic), headache, fever. Rarely, hypersensitivity, tamponade, ARDS. Monitor: FBC* (baseline plus 2–4 h, 12 h and 24 h after giving) and clotting (baseline at least).
Dose: 250g/kg iv over 1 min, then 0.125g/kg/min (max 10 g/min) ivi NB: give through iv pyrogenic filter and needs concurrent heparin. Specialist use only: get senior advice or contact on-call cardiology.
Acarbose
Oral hypoglycaemic:
alpha-glucosidase inhibitor. Delays digestion and ↓s absorption of starch and sucrose (also ⇒ ↓postprandial
hyperglycaemia in type 1 DM).
ALENDRONATE (ALENDRONIC ACID)
Bisphosphonate: ↓s osteoclastic bone resorption.
Use: osteoporosis Rx and Px (esp if on corticosteroids).
CI: delayed GI emptying (esp achalasia and oesophageal stricture/other abnormalities), ↓Ca2, unable to sit/stand upright 30 min, R(if severe)/P/B.
Caution: upper GI disorders (inc gastritis/PU) R.
SE: oesophageal reactions*, GI upset/distension, ↓Ca2, ↓PO4 (transient), PU, hypersensitivity (esp skin reactions), myalgia. Rarely osteonecrosis and femoral stress fractures (discontinue drug and should receive no further bisphosphonates).
#Warn: _take with full glass of water on an empty stomach 30 min before, and stay upright until breakfast*. Stop tablets and seek medical attention if symptoms of oesophageal irritation develop._
Dose: 5–10 mg mane (10 mg od dosing can be given as once-wkly 70-mg tablet if for post-menopausal osteoporosis)
ALISKIREN
DIrect Renin inhibitor
Allopurinol
Xanthine oxidase inhibitor: ↓s uric acid synthesis.
Use: Px of gout, renal stones (urate or Ca2 oxalate) and other hyper-urate states (esp 2° to chemotherapy).
SE: GI upset,severe skin reactions(stop drug if rash
develops and allopurinol is implicated– can reintroduce cautiously
if mild reaction and no recurrence). Rarely, neuropathy (and many
non-specific neurological symptoms), blood disorders, RF, hepatotoxicity, gynaecomastia, vasculitis.
Warn: report rashes, maintain good hydration.
Interactions: ↑s fx/toxicity of azathioprine (and possibly other
cytotoxics, esp ciclosporin), chlorpropamide and theophyllines.
Level ↓d by salicylates and probenecid. ↑rash with ampicillin and
amoxicillin.
Initial Rx can ↑gout: give colchicine or NSAID (e.g. indometacin or diclofenac – not aspirin) Px until 1 month after urate normalised.
AMILORIDE
K-sparing diuretic (weak): inhibits DCT Na reabsorption and K excretion.
Use: oedema (2° to HF, cirrhosis or ↑aldosterone), HTN (esp in conjunction with ↑K-wasting diuretics as combination preparations;
CI: ↑K, R.
Caution: DM (as risk of RF; monitor U&E), ↑risk of acidosis, ↓Na P/B/E.
SE: ↑K, GI upset, headache, dry mouth, ↓BP (esp postural), ↓Na, rash, confusion. Rarely encephalopathy, hepatic/renal
dysfunction.
Interactions: ↑s lithium levels. Can ↑nephrotoxicity of NSAIDs.
Dose: 2.5–20 mg od (or divide into bd doses).
Beware if on other drugs that ↑K, e.g. spironolactone, triamterene, ACE-i, ARBs and ciclosporin. Don’t give oral K
supplements inc dietary salt-substitute tablets
amiodarone
Class III antiarrhythmic: ↑s refractory period of conducting system;
useful as has ↓negative inotropic fx than other drugs and can give when others ineffective/CI.
Use: tachyarrhythmias: esp paroxysmal SVT, AF, atrial flutter, nodal tachycardias, VT and VF. Also in CPR/periarrest arrhythmias.
CI: ↓HR (sinus), sinoatrial HB, SAN disease or severe conduction
disturbance w/o pacemaker, Hx of thyroid disease/iodine
sensitivity, P/B.
Caution: porphyria, ↓K (↑risk of torsades), L/R/H/E.
SE:
Acute: N&V (dose-dependent), ↓HR/BP.
Chronic: rarely but seriously ↑or ↓T4, interstitial lung disease (e.g. fibrosis, but reversible if caught early), hepatotoxicity, conduction disturbances (esp ↓HR).
Common: malaise, fatigue, photosensitive skin (rarely ‘grey-slate’),
corneal deposits‘night glare’ (reversible),tremor, sleep disorders.
Less commonly: optic neuritis (rare but can ↓vision), peripheral
neuropathy, blood disorders, hypersensitivity.
Monitor: TFTs and LFTs (baseline then 6-monthly). Also baseline K and CXR (watch for ↑SOB/alveolitis).
Warn: avoid sunlight/use sunscreen (inc several months after stopping).
Interactions: ↑s fx of phenytoin and digoxin. Other class III and many class Ia antiarrhythmics, antipsychotics, TCAs, lithium, erythromycin, co-trimoxazole, antimalarials, nelfinavir, ritonavir ⇒ ↑risk of ventricular arrhythmias. Verapamil, diltiazem and -blockers ⇒ ↑risk of ↓HR and HB W.
Dose: po: load with 200 mg tds in 1st wk, 200 mg bd in 2nd wk,
then (usually od) maintenance dose according to response (long t1/2:
months before steady plasma concentration)
NB: initiate in hospital
or specialist outpatient service; iv: (extreme emergencies only)
150–300 mg in 10–20 ml 5% glucose over 3 min (don’t repeat for
at least 15 min); ivi: 5 mg/kg over 20–120 min (max 1.2 g/day).
For use in cardiac arrest/periarrest arrhythmias see ALS and
tachycardia algorithms in the front and back cover flaps of this book
respectively.
iv doses: give via central line (if no time for insertion, give via
largest Venflon possible) with ECG monitoring. Avoid giving if severe respiratory failure or ↓BP (unless caused by arrhythmia) as can worsen. Avoid iv boluses if CCF/cardiomyopathy
AMLODIPINE
Ca2 channel blocker (dihydropyridine): as nifedipine, but ⇒ no ↓contractility or ↑HF.
Use: HTN, angina (esp ‘Prinzmetal’s’ coronary vasospasm).
CI: ACS, cardiogenic shock, significant aortic stenosis, acute porphyria, P/B.
Caution: BPH (poly-/noc-turia), L.
SE: as nifedipine but ↑ankle swelling and possibly ↓vasodilator fx (headache, flushing and dizziness).
Interactions: less than other Ca2 channel blockers but may ↑fx
of theophyllines and care needed with inducers of cytochrome 3A4.
Dose: initially 5 mg od po (if required to 10 mg). NB: consider
↓dose in LF.
Atenolol
beta-blocker: (mildly) cardioselective* (1 2), ≠H2O solubility
Øcentral fx** and ≠renal excretion***.
Use: HTN1 (for advice on stepped HTN Mx see p.174), angina2,
MI (w/in 12 h as early intervention)3, arrhythmias4.
CI/Caution/SE/Interactions: see Propranolol ⇒ Øbronchospasm*
(but avoid in all asthma/only use in COPD if no other choice) and
Øsleep disturbance/nightmares**.
Dose: 25–50 mg od po1; 100 mg od po2; 5 mg iv over 5 min then
50 mg po 15 min later then start 50 mg bd 12 h later3; 50–100 mg od
po4 (for iv doses see SPC/BNF). NB: consider Ødose in RF***.
BENDROFLUMETHIAZIDE
Thiazide diuretic: ↓s Na (and Cl) reabsorption from DCT ⇒ Na and H2O loss and stimulates K excretion.
Use: oedema (2° to HF or low–protein states), HTN2 (in short term by ↓ing fluid volume and CO; in long term by ↓ing TPR
Px against renal stones in hypercalciuria.
CI: ↓K (refractory to Rx), ↓Na, ↑Ca2, Addison’s disease, ↑urate (if symptoms), L/R (if either severe, otherwise caution).
Caution: porphyria, and can worsen gout, DM or SLE, P/B/E.
SE: dehydration (esp in elderly), ↓BP (esp postural), ↓K, GI upset, impotence, ↓Na, alkalosis (with ↓Cl), ↓Mg2, ↑Ca2,
↑urate/gout, ↑glucose, lipid metabolism (esp ↑cholesterol), rash, photosensitivity, blood disorders (inc ↓Pt, ↓NØ), pancreatitis, intrahepatic cholestasis, hypersensitivity reactions (inc severe respiratory and skin reactions), arrhythmias.
Interactions: ↑s lithium levels. fx ↓by NSAIDs and oestrogens. If ↓K can ↑toxic fx of many drugs (esp digoxin, NSAIDs,
corticosteroids and many antiarrhythmics). ↑risk of ↓Na with carbamazepine and amphotericin.
Dose: initially 5–10 mg mane po, then ↓dose frequency (i.e. omit days) if possible; 2.5 mg od po (little benefit from ↑doses).
BENZYLPENICILLIN ( PENICILLIN G)
Penicillin with **poor po absorption** \>\> only given im/iv: used mostly against streptococcal (esp S. pneumoniae) and neisserial (esp N. gonorrhoeae, N. meningitidis) infections.
BEZAFIBRATE
Fibrate (lipid-lowering): ⇒ ↓TG, ↓LDL, ↑HDL by stimulating lipoprotein lipase (⇒ ↓conversion of VLDL/TG to LDL and ⇒
↑LDL clearance from circulation). Also ⇒ (mild) ↓cholesterol.
Use: hyperlipidaemias (esp if ↑TG types IIa/b, III, IV, V).
CI: gallbladder disease, PBC, ↓albumin (esp nephrotic syndrome), R*/L (if either severe; otherwise caution), P/B.
Caution: ↓T4 (needs to be corrected).
_SE:_ **GI upset, ↓appetite, gallstones, myositis** (rarer but important: ↑risk if RF\*). Also impotence, rash (inc pruritus, urticaria), headache. Rarer: dizziness, vertigo, fatigue, hair loss, blood disorders (↓Hb, ↓WCC, ↓Pt).
I_nteractions:‘statins’ ⇒ ↑risk of myositis. ↑s fx of
antidiabetics._
↑risk of hepatotoxicity with MAOIs. Can ↑renal
toxicity of ciclosporin. W.
Dose: 200 mg tds po (after food). MR 400 mg od preps
availableBNF. NB: ↓dose in RF.
BUMETANIDE
Loop diuretic: inhibits Na/K pump in ascending loop of Henle.
Use/CI/Caution/SE/Monitor/Interactions: as furosemide; also
headaches, gynaecomastia and at ≠doses can ⇒ myalgia.
Dose: 1 mg mane po (500g may suffice in elderly), ≠ing if
required (5 mg/24 h usually sufficient; ≠by adding a lunchtime dose,
then ≠ing each dose). 1–2 mg im/iv (repeat after 20 min if required).
2–5 mg ivi over 30–60 min.
NB: give iv in severe oedema; bowel oedema ⇒ Øpo absorption.
