Drugs Flashcards
ACE Inhibitors / Angiotensin II Antagonists
Prescribed for:
Heart failure, hypertension
ACE inhibitor examples:
Ramipril, lisinopril, captopril.
Angiotensin II antagonist examples:
Losartan, candesartan.
ACE Contraindications:
Pregnancy / breastfeeding,
previous allergic reaction to ACE inhibitor.
ACE side effects
Hyperkalaemia, postural
hypotension, constipation, diarrhoea, nausea, vomiting.
Specific side effects: ACE inhibitors cause a persistent dry cough (due to rise in bradykinin) and angioedema.
Avoid potassium rich diets if not taking a drug which lowers potassium alongside (e.g., a thiazide or loop diuretic).
Statins
Hypercholesterolaemia (incl. familial),
hypertriglyceridemia, prevention of cardiovascular
events in those with atherosclerotic disease or diabetes
Statin examples
Simvastatin, Atorvastatin, Pravastatin, Rosuvastatin.
Statin mode of action
Competitively inhibits HMG CoA reductase an enzyme involved in cholesterol (and COQ10) synthesis.
Statin contraindications
Pregnancy, breastfeeding, liver disease.
Statin caution
High alcohol intake, liver disease history.
Statin Side effects
GIT disturbance, headaches, fatigue , insomnia, myositis
(inflammation of muscles), statin induced myopathy
*
Statin use can lead to rhabdomyolysis the breakdown of muscle cells. This can result in kidney disease and even failure. E xtra care needed with foods / supplements that may interfere with metabolism.
Statin Interactions
Important interactions with other drugs, so do check your medicine resources!
Grapefruit juice / pomegranate juice:
Significantly increases GI absorption of CYP3A4
substrates and increases peak levels of statins.
This combination should be completely avoided.
Statin: Nutrient depletion
CoQ10 (watch for muscle pain / fatigue).
Statin alternative
Red yeast rice: A combination of mevinic
acids and derivatives e.g., monacolin K (identical to the active in Lovastatin), and other constituents that exhibit cholesterol lowering activity. Combining with statins may increase overall side effects.
Diuretics
Prescribed for: Oedema due to heart failure, hypertension
Diuretics Examples
Furosemide (loop diuretic),
bendroflumethiazide (thiazide diuretic).
Spironolactone (potassium sparing diuretic).
Diuretics Mode of action
Inhibit reabsorption of filtrate from various
sections of the nephron (i.e., increased urine output), decreasing blood volume and pressure.
Diuretics contraindications
Metabolic imbalances
(hypokalaemia,
hyponatraemia,
hypercalcaemia), Addison’s disease.
Diuretics Caution
Exacerbates diabetes, gout and SLE. Elderly are susceptible to side effects!
Diurectics Side Effects
Hypokalaemia (can be dangerous), hypotension, GIT disturbance, impotence. Milk alkali syndrome may occur when thiazides are combined with large quantities of calcium carbonate!
Diurectics alternative
Taraxacum officinalis
——(dandelion) Acts as a diuretic but also supplies potassium (the leaf), unlike most pharmaceutical diuretics.
Digoxin
Prescribed for:
Atrial fibrillation, heart failure:
Digoxin: Mode of Action
Increases force of myocardial contraction and reduces conductivity within the atrio ventricular node.
Digoxin: Contraindications
Heart block, ventricular tachycardia.
Digoxin: Caution
Hypokalaemia and low blood magnesium can increase the risk of toxicity from digoxin!
Digoxin: Side Effects
Nausea, vomiting, diarrhoea, loss of appetite, abdominal pain, visual disturbance, arrhythmias. The elderly are especially susceptible to side effects.
Digoxin: Interactions
Hawthorn can increase myocardial contraction.
Concomitant use may require digoxin’s dose to be reduced.
Antacids
Prescribed for:
Gastro oesophageal reflux
disease (GORD), indigestion:
Antacids: Examples
Calcium carbonate, magnesium, aluminium
Antacids: Mode of Action
Neutralisation : acid + base = water + salt.
Antacids: Caution
Low gastric HCl. Overuse can result in a rebound effect if the drug is
discontinued (the acid comes back more strongly)
Antacids: Side effects
Impaired nutrient absorption; magnesium versions can be laxative,
aluminium versions can be constipating.
Antacids: Interactions
Vit. D may ↑ aluminium
absorption if taken at the same time.
Antacids: Alternatives
Diet and lifestyle changes:
Chew food well, fluids away from meals;
demulcent / anti-inflammatory herbs ― aloe vera juice, slippery elm, liquorice, marshmallow root ; avoid caffeine, lose weight if needed, stop smoking; manage stress e.g., breathing exercises to support a shift into a parasympathetic state.
Proton Pump Inhibitors
Prescribed for: Gastro- oesophageal reflux disease (GORD), prevention of NSAID associated ulcers, triple therapy with antibiotics for gastric / duodenal ulceration.
PPI: Examples
Omeprazole, lansoprazole, esomeprazole.
PPI: Mode of Action
Blocks gastric cells proton (hydrogen) pump.
PPI: Cautions
Liver disease, pregnancy,
breast feeding, gastric cancer (masks symptoms)
PPI: Side effects
Headache, GI disturbances,
rebound gastric hypersecretion and
heartburn after discontinuation of drug.
PPI: Long term side effects
- Increased risk of GI infections (e.g., Clostridium difficile ) and SIBO. Alkaline
gastric pH allows bacterial survival. - Increased fracture risk : Reduced calcium absorption leads to decreased bone mineral density, possible inhibition of osteoclast activity.
- Vitamin B12 deficiency : Gastric acid is needed for release of vit. B12 from proteins to help intestinal absorption.
- Low blood magnesium due to decreased intestinal absorption. Also reduced iron absorption (= possible iron deficiency anaemia).
PPI Withdrawal for GORD
PPI withdrawal depends upon several factors including the dose and duration of treatment. Sudden withdrawal may
cause rebound reflux. The 5R approach supports clients to reduce and withdraw from PPIs over a period.
Anti
coagulants: Warfarin
Prescribed for:
DVT, pulmonary
embolism, transient ischaemic attacks:
Warfarin: Mode of Action
Antagonises the effects of vitamin K a co factor for the production of four clotting factors.
Warfarin: Contraindications
Haemophilia, cerebral thrombosis, peptic ulcers, hypertension, pregnancy.
Warfarin: Cautions
Surgery, Liver / Kidney
impairment, breastfeeding.
Warfarin: Side effects
Haemorrhage is the worrying side effect!
Warfarin: Interactions
Major changes in diet (salads / green vegetables)
and alcohol consumption can affect anticoagulant control.
* Pomegranate juice increases the INR by inhibiting the CYP450 enzyme that metabolises warfarin .
* High doses of vitamin E inhibit platelet aggregation and should be avoided with warfarin.
Levothyroxine
Hypothyroidism
Levothyroxine: Mode of action
Life long replacement
Levothyroxine: Contra-indications
Thyrotoxicosis
Levothyroxine: Cautions
Elderly, cardiovascular disorders.
Levothyroxine: Side effects
Headache, insomnia, tremor, anxiety, flushing.
Levothyroxine: Dosage
The dose should be taken 30-60 minutes pre breakfast or caffeine containing liquids to avoid reduced absorption.
Levothyroxine: Interactions
Oral iron and calcium supplements (and cow’s
dairy) reduce the absorption of levothyroxine. It is important that doses are separated by at least four hours.
Antidepressants - SSRIs
Prescribed for:
Depressive illness, post traumatic stress, obsessive compulsive disorder:
SSRIs
Sertraline, citalopram, fluoxetine.
SSRIs - Mode of Action
Selectively inhibit the re uptake of serotonin (5- hydroxytryptamine, 5 HT).
SSRIs: Contraindications
Poorly controlled epilepsy.
SSRIs: Side Effects
GIT disturbance, constipation, diarrhoea, insomnia, anxiety, agitation, sexual dysfunction, reduced appetite.
Serotonin Syndrome
The serotonin syndrome is associated with an
excess of serotonin due to therapeutic drug
use, overdose or interactions between drugs:
* Although rare, it can be fatal.
* It can occur when two or more drugs affecting serotonin are given at the same time or after one serotonergic drug is
stopped and another started.
* Special care is needed when switching from an SSRI to an MAOI (mono amine oxidase inhibitor) or vice versa.
* Symptoms include confusion, disorientation, exaggerated reflexes,
abnormal movements, fever, sweating, hypo / hypertension.
* Two important
supplements: 5 HTP
and St. John’s wort must not be combined with SSRIs as the additive effect significantly increases
the risk of serotonin syndrome.
NSAIDs
Prescribed for:
Pain relief, inflammation, temperature reduction:
NSAIDs: Examples
Ibuprofen, diclofenac, naproxen.
NSAIDs: Mode of Action
Inhibits the activity of cyclooxygenases (COX 1 and COX 2), thereby inhibiting prostaglandin synthesis.
NSAIDS: Contra-indications
Peptic ulceration, history of gastrointestinal bleeding or hypersensitivity to
aspirin, IBD.
NSAIDs: Cautions
Asthma, cardiac impairment, impaired renal function.
NSAIDs: Side effects
- Inhibit prostaglandins that play a vital role in gastric mucosal defence , increasing the risk of gastric bleeding and ulceration.
- Block renal prostaglandins that normally dilate vessels
in the kidneys . This can lead to reduced blood flow
and oxygen supply causing acute kidney damage
NSAIDs: Alternatives
- Willow bark ( Salix alba ) reduces inflammation
and fever and has analgesic properties. - Willow bark does not have antiplatelet activity and can be safely used alongside NSAIDs where pain is more severe.
- Turmeric (curcumin), g inger and b o swellia are also COX inhibitors.
- Ensure an anti inflammatory / alkalising diet incorporating a
range of fruit and vegetables rich in flavonoids and chlorophyll. - Quercetin inhibits LOX and COX pathways and down regulates NF-kB . Food sources include onions, asparagus, apples, berries
Corticosteroids
Prescribed for:
Asthma, eczema, IBD,
hypersensitivity reactions, autoimmune conditions
Sterioids: Examples
Prednisolone, hydrocortisone.
Steroids: Mode of Action
Modulates protein synthesis by binding to DNA. It stimulates the production of a glycoprotein called lipocortin, which inhibits the activity of phospholipase A2 and hence inflammatory mediators.
Steroids: Contraindications
Active infection, live virus vaccination.
Steroids: Side Effects
Long term systemic use increases risk of Cushing’s
syndrome, diabetes mellitus, osteoporosis and infections.
Steroids: Alternatives
Alternative approach: Anti inflammatory diet;
nutrients and herbs that inhibit inflammatory
mediators e.g., EFAs, quercetin, turmeric, ginger.
* Liquorice root has been shown to modify or even
increase the body’s levels of cortisol . Liquorice, if given in large quantities with corticosteroids, may cause additive hypokalaemia.
Pharmacodynamic interactions are possible with liquorice and
fludrocortisone due to mineralocorticoid effects, and with liquorice and medicines that deplete potassium levels such as diuretics.
