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Clinical Pharmacology and Prescribing > Top 100 Drugs > Flashcards

Top 100 Drugs Flashcards

1
Q

Side Effects - Sodium Valporate

A

Valproate
Appetite increase, so weight gain
Liver failure (monitor LFTs during 1st 6 months)
Pancreatitis
Reversible hair loss (grows back curly, apparently)
Oedema
Ataxia
Teratogenicity, Tremor, Thrombocytopaenia
Encephalopathy (due to hyperammonaemia) / Enzyme inducer
Has the greatest risk of fetal abnormalities

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2
Q

Indications - Sodium Valporate

A

Seizure prophylaxis in epilepsy

Manic episodes in bipolar disorder - used as prophylaxis against recurrence

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3
Q

Contraindications - Sodium Valporate

A

Women of child-bearing age - especially time of conception and pregnancy
Hepatic Impairment
Renal impairment

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4
Q

Aminosalicylates - Indications

A

Mesalazine - 1st line mild/moderate UC

Sulfasalazine - Used with a DMARD in rheumatoid arthritis

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5
Q

Side Effects - Aminosalicylates

A

Nausea
Dyspepsia
Headache
Blood Abnormalities - leucopenia and thrombocytopenia (rare)
Oligospermia
Can cause severe hypersensitivity reactions

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6
Q

Contraindications - Aminosalicylates

A

Not given to those with aspirin hypersensitivity

Mesalazine - pH sensitive coating - affected by PPIs and Lactulose

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7
Q

PPI - Indications

A

Peptic ulcer disease
NSAID-associated ulcers
Symptomatic relief of dyspepsia and GORD
H. pylori infection

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8
Q

PPI - Mechanism

A

Irreversibly inhibit H+/K+ ATPase in gastric parietal cells

Suppress gastric acid production almost completely

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9
Q

PPI - Adverse effects

A

GI disturbances
Headache
Prolonged treatment - hypomagnesaemia - severe can lead to tetany

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10
Q

PPI - Warnings

A

May disguise symptoms of gastro-oesophageal cancer

Cautioned in those with osteoporosis - increased risk of fracture

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11
Q

PPI - Interactions

A

Reduce antiplatelet affect of clopidogrel by decreasing its activation of cytochrome P450 enzymes

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12
Q

Metronidazole - Indications

A

Antibiotic-associated colitis - gram-positive anaerobe Clostridium difficile
Oral Infections / Aspiration pneumonia
Surgical and gynae infections by gram-negative anaerobes
Protozoal infections - trichomonal vaginal infection, amoebic dysentery and giardiasis

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13
Q

Metronidazole - Mechanism

A

Anaerobic Bacteria - DNA degradation and cell death (bactericidal)

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14
Q

Metronidazole - Adverse Effects

A

GI upset (nausea and vomiting)
Delayed Hypersensitivity reactions -
Can cause peripheral and optic neuropathy, seizures and encephalopathy

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15
Q

Metronidazole - Warnings

A

Metabolised by P450 enzymes - reduced in people with severe liver disease
Inhibits acetaldehyde dehydrogenase - responsible for clearing alcohol metabolite
Alcohol should not be drunk while taking metronidazole

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16
Q

Metronidazole - Interactions

A

Some inhibitory effect on CYP enzymes

Reduction in warfarin metabolism and phenytoin

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17
Q

Cephalosporins - examples?

A

Ceftriaxone, Cefalexin, Meropenem, Ertapenem

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18
Q

Ceftriaxone - Mechanism

A

3rd generation cephalosporin
Broad-spectrum - long half-life
Penetrates the meninges, eyes and inner ear
Used in the treatment of bacterial infections caused by susceptible usually gram-positive
Ceftriaxone works by inhibiting the mucopeptide synthesis in the bacterial cell wall
Prevents them from maintaining an osmotic gradient leading to bacterial cell swelling and death
Has in vitro activity against gram-positive aerobic, gram-negative aerobic, and anaerobic bacteria
Bactericidal activity of ceftriaxone results from the inhibition of cell wall synthesis and is mediated through ceftriaxone binding to penicillin-binding proteins (PBPs)
Ceftriaxone is stable against hydrolysis by a variety of beta-lactamases, including penicillinases, and cephalosporinases and extended-spectrum beta-lactamases

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19
Q

Ceftriaxone - Cautions

A

Ceftriaxone should not be mixed with or giving in the same IV line as diluents/products containing calcium as they may cause ceftriaxone to precipitate.
In those at increased C. difficile infection
Epilepsy
Cautioned in those with renal impairment

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20
Q

Ceftriaxone - Adverse Effects

A

Ceftriaxone use may also cause biliary sludge or gallbladder pseudolithiasis.
GI upset
Antibiotic associated colitis -> can lead to bowel perforation and death
Clostridium difficile infections
Hypersensitivity -> Cross-reactivity can occur in penicillin allergic patients

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21
Q

Ceftriaxone - Interactions

A

Enhance anticoagulant effects of warfarin by killing normal gut flora that synthesise vitamin K
Increase nephrotoxicity of aminoglycosides
Reduce conc. of valproate

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22
Q

Methotrexate - Mechanism

A

DMARD for rheumatoid arthritis
Chemotherapy regimen for cancers: leukaemia, lymphoma and some solid tumours
Treatment of severe psoriasis
Mechanism of action
Folic analogue inhibits dihydrofolate reductase (which converts dietary folate to tetrahydrofolate -needed for DNA synthesis) and thymidylate synthase - reduce production of thymine needed for DNA synthesis –> prevents cellular replication
Anti-inflammatory and immunosuppressive - inhibition of inflammatory mediators IL-6, IL-8 and TNF-alpha
Reduction in methionine

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23
Q

Methotrexate - Adverse Effects

A

Mucosal damage
Bone marrow suppression (can lead to neutropenia and increased infection risk)
Hypersensitivity reactions - cutaneous reactions, hepatitis, pneumonitis
Long term can lead to hepatic cirrhosis or pulmonary fibrosis
Renal failure and hepatic toxicity
Risk of accidental overdose - treated with folinic acid which rescues normal cells from methotrexate effects along with hydration and urinary alkalinisation - enhance excretion

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24
Q

Methotrexate - Contraindicated

A

Teratogenic - avoided in pregnancy (both men and women)
Severe renal impairment
Abnormal liver function

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25
Q

Methotrexate - Interactions

A

Toxicity likely with drugs that can inhibit its renal excretion - NSAIDs, penicillins
Co-prescription with other folate antagonists (Trimethoprim and phenytoin) can lead to haematological abnormalities

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26
Q

Dexamethasone (Glucocorticoids - systemic corticosteroids) - Mechanism

A

Used to treat allergic or inflammatory disorders
Suppression of autoimmune disease
Cancer treatment as part of chemotherapy or to reduce tumour associated swelling
Hormone replacement in adrenal insufficiency or hypoparathyroidism
Mechanism of Action
Bind to the glucocorticoid receptor - inhibiting pro-inflammatory signals (cytokines and TNF-alpha) and promoting anti-inflammatory signals
Decreased vasodilation and permeability of capillaries
Suppression of circulating monocytes and eosinophils
Gluconeogenesis from increased circulating fatty acids and amino released by fat and muscle catabolism
Mineralocorticoid effect - Na+ retention and K+ excretion

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27
Q

Dexamethasone (Glucocorticoids - systemic corticosteroids) - Adverse Effects

A

Immunosuppression - increases the risk and severity of infection - alters host response
Increased catabolism - proximal muscle weakness, skin thinning with easy bruising and gastritis
Mood and behavioural changes - insomnia, confusion, psychosis
Hypertension, hypokalaemia and oedema
Suppresses ACTH production - in prolonged treatment leads to adrenal atrophy
If steroids are withdrawn too quickly - Addisonian crisis
Needs to be withdrawn slowly by can cause symptoms of chronic glucocorticoid deficiency
Cannot produce cortisol secretion in response to stress - needs to be provided artificially in acute illness (double dose)

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28
Q

Dexamethasone (Glucocorticoids - systemic corticosteroids) - Contraindicated

A

§ Those with infection

§ Children

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29
Q

Dexamethasone (Glucocorticoids - systemic corticosteroids) - Interactions

A

Peptic ulcers and GI bleeding - especially if used with NSAIDs
Hypokalaemia enhancement with those on Beta-2 agonists, theophylline (PDE inhibitor), loop and thiazide diuretics
Efficacy reduced by cytochrome P450 inducers (phenytoin, carbamazepine, rifampcin)

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30
Q

Calcium Gluconate - Indications

A

Used in beta blocker and Calcium Channel Toxicity
Severe acute hypocalcaemia or hypocalcaemic tetany
Acute severe hyperkalaemia (plasma-potassium concentration above 6.5 mmol/litre or in the presence of ECG changes)
Calcium deficiency, Mild asymptomatic hypocalcaemia
Hyperkalaemia is common among hospital inpatients
First line emergency treatment for severe hyperkalaemia associated with ECG abnormalities

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31
Q

Calcium Gluconate - Dosage

A

10mL of calcium gluconate 10% IV over 10-15 minutes

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32
Q

Calcium Gluconate - Mechanism of Action

A

○ In hyperkalaemia - calcium raises the myocardial threshold potential, reducing excitability and the risk of arrhythmias - no effect on serum potassium

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33
Q

Calcium Gluconate -Contraindicated

A

Conditions associated with hypercalcaemia (e.g. some forms of malignant disease)

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34
Q

Allopurinol - Indications

A

Prevent recurrent attacks of gout
Thiazide or loop diuretics - increases serum uric acid
Aspirin inhibits renal excretion of uric acid
Drug-induced gout C
Prevent uric acid and calcium oxalate renal stones
Prevent hyperuricaemia and tumour lysis syndrome

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35
Q

Allopurinol - Mechanism of Action

A

Xanthine oxidase inhibitor

Xanthine oxidase metabolises xanthine from purines to uric acid

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36
Q

Allopurinol - Adverse Effects

A

Initially can worsen gout attacks - can be prevented with co-prescription with an NSAIDs or colchicine during initiation of treatment
Allopurinol hypersensitivity syndrome - rare
Can cause Stevens-Johnson Syndrome or toxic epidermal necrolysis

37
Q

Allopurinol - Cautions

A

Shouldn’t be started during acute attacks of gout but can be continued if patient is already on it
Renal and hepatic impairment

38
Q

Allopurinol - Interactions

A 
Active metabolite (mercaptopurine) - of the pro-drug azathioprine metabolised by xanthine oxidase 
Co-prescription with ACE inhibitors or thiazides can increase risk of hypersensitivity and with amoxicillin can increase the risk of skin rash
39
Q

Rasburicase - Mechanism of Action

A

Recombinant form of urate-oxidase enzyme used to treat hyperuricemia following chemotherapy for leukaemias and non-Hodgkin’s lymphoma.
Rasburicase catalyzes enzymatic oxidation of uric acid into an inactive and soluble metabolite (allantoin).
The injection of rasburicase reduces levels of uric acid and mitigates the toxic effects of chemotherapy induced tumour lysis

40
Q

Rasburicase - Contraindicated

A

G6PD deficiency

41
Q

Rasburicase - Cautioned

A

Atopic Allergies

42
Q

Rasburicase - Adverse Effects

A

Diarrhoea, fever, headache, nauseas, skin reactions, vomiting
Haemolytic anaemia, hypersensitivity, hypotension

43
Q

Piptazobactam - Interactions

A

Antipseudomonal penicillins -> reserved for severe infections (antibiotic resistance or in immunocompromised (neutropenic) individuals)
Tazobactam is the beta - lactamase inhibitor (confers activity against beta-lactam producing Staphylococcus aureus and gram-negative anaerobes)
Clinical infections treated:
LRTIs
UTIs
Intraabdominal sepsis
Skin and soft tissue infections

44
Q

Piptazobactam - Mechanism of Action

A

Responsible for cross-linking peptidoglycan in bacterial cell walls - weakens walls preventing them from maintaining their osmotic gradient

45
Q

Piptazobactam - Adverse Effects

A

GI upset - nausea and diarrhoea
Clostridium difficile
Rare- antibiotic - associated colitis

46
Q

Piptazobactam - Warnings

A

Cautioned in those with a C. difficile infection
Contraindicated in penicillin allergy
People with penicillin allergy would react to cephalosporins and other B-lactam antibiotics

47
Q

Piptazobactam - Interactions

A

Pencillins reduce renal excretion of methotrexate - can increase toxicity
Enhance anticoagulant effects of warfarin by killing normal GI flora that synthesise vitamin K
Each dose of piperacillin - tazobactam contains 11mmol Na+ and is infused in 50-150mL fluid - needs to be considered when prescribing fluids in heart failure patients

48
Q

Gentamicin - Aminoglycoside - Indications

A

Used to treat severe infections - caused by gram-negative aerobe (including pseudomonas aerunginosa):
□ Severe sepsis
□ Pyelonephritis and complicated UTIs
□ Biliary and other intraabdominal sepsis
□ Endocarditis
Topical - bacterial skin and ear infections

49
Q

Gentamicin - Aminoglycoside - Warnings

A

Has a very narrow therapeutic index - little safety margin between clinically effective dose and toxic dose - aminoglycosides distribute through body water not fat - needs to be the basis of the dosage given
Warnings:
□ Renally excreted
□ Not be given in patients with myasthenia gravis
□ Neonates, elderly patients and those with renal impairment

50
Q

Gentamicin - Aminoglycosides - Mechanism of Action

A

Mechanism of Action
Against gram-negative aerobic bacteria - some activity against staphylococci and mycobacteria - other agents preferred in practice
Inactive against streptococci and anaerobes - need to be combined with penicillin and/or metronidazole - when organism is unknown
Binds irreversibly to bacterial ribosomes (30S subunit) - inhibit protein synthesis -inhibit protein synthesis
Are bactericidal
As pencillins weaken bacterial cell walls - may enhance aminoglycoside - increase bacterial uptake via oxygen - dependent transport system which streptococci and anaerobic bacteria don’t have

51
Q

Gentamicin - Aminoglycosides - Adverse Effects

A

Nephrotoxicity (reduced urine output and rising serum creatinine and urea) can be reversible and otoxicity (hearing loss, tinnitus or vertigo) is irreversible - accumulate in tubular epithelial cells and cochlear and vestibular hair cells - trigger apoptosis and cell death

52
Q

Gentamicin - Aminoglycosides - Interactions

A

Ototoxicity more likely if co-prescribed with loop diuretics (e.g. furosemide) or vancomycin
Nephrotoxicity more likely is co-prescribed with ciclosporin, platinum chemotherapy, cephalosporins or vancomycin

53
Q

Anti-muscarinics, bronchodilators - Indications

A

COPD - short acting muscarinics - relieve breathlessness (brought on by exercise or during exacerbations)
LAMAS - used to prevent breathlessness and exacerbations
Asthma - short-acting anti-muscarinic used to help relieve breathlessness during acute exacerbations (added to a short -acting beta-2- agonist e.g. salbutamol).
LAMAs (tiotroprium) - added to high dose inhaled corticosteroids and long-acting beta-2 agonists (LABA) as maintenance treatment - patients 1 or more severe asthma exacerbations in the past year

54
Q

Anti-muscarinics, bronchodilators - Examples

A

Ipratropium, tiotropium, Glycopyrronium, Aclidinium

55
Q

Anti-muscarinics, bronchodilators - Mechanism of action

A

Competitive inhibitor of acetylcholine
Reduce smooth muscle tone, including the respiratory tract and bladder and reduce secretions from the glands in the respiratory and GI tracts
Relaxation of the pupillary constrictor and ciliary muscles - pupil dilation + prevent accommodation
No advantaged in prescribing more than 4 times daily

56
Q

Anti-muscarinics, bronchodilators - Adverse Effects

A

Inhaled - rapidly metabolised - less effects
Nasopharyngitis, sinusitis and cough, GI disturbance (including dry mouth and constipation and urinary retention, blurred vision and headaches)

57
Q

Anti-muscarinics, bronchodilators - Warnings

A

Cautioned in patients with - angle - closure glaucoma (can cause a rise in intra-ocular pressure)
Cautioned in patients with urinary retention and arrhythmias

58
Q

Beta 2 Agonists - Indications

A

Asthma - SABAs relieve breathlessness
LABAs used in chronic asthma when inhaled corticosteroids are insufficient - need to be given with inhaled corticosteroids
COPD - SABAs relieve breathlessness
LABAs 2nd line therapy of COPD - improve symptoms and reduce exacerbations
Hyperkalaemia - neubulised used to lower serum potassium (given along with insulin and glucose and calcium gluconate to stabilise the myocardium)

59
Q

Beta 2 Agonists - Mechanism of Action

A

Smooth muscles relaxation - G - protein coupled receptors
Stimulate Na+/K- ATPase pumps on cell surface - K+ shifts from extracellular to intracellular compartments
Useful adjunct in hyperkalaemia - not used in isolation

60
Q

Beta 2 agonist - Adverse effects

A

Flight or fight - tachycardia, palpitations, anxiety and tremor
Glycogenolysis - increase serum glucose
High dose - serum lactate goes up
Long term - muscle cramps

61
Q

Beta 2 agonist - Warnings

A

LABA - only used with an inhaled corticosteroid

Cautioned in those with CVS risks - can induce tachycardias or arrhythmias

62
Q

Beta 2 agonists - Interactions

A

Beta-blockers
High nebulised doses of beta - 2 agonists with theophylline and corticosteroids - lead to hypokalaemia - serum K+ needs to be monitored

63
Q

Beta 2 agonists - Nebuliser Therapy

A

Indicate whether the nebuliser should be driven by oxygen or air
Oxygen should be used in asthma whereas medical air should be used in COPD - due to risk of CO2 retention

64
Q

Inhaled Corticosteroids - Indications

A

Asthma - treat airway inflammation (usually combined with SABA)
COPD - Control symptoms and prevent exacerbations - people with severe airway obstruction on spirometry and recurrent exacerbations (usually combined with a LABA)

65
Q

Inhaled Corticosteroids - Mechanisms of Action

A

Reduction in mucosal inflammation, widens the airways and reduced mucus secretion

66
Q

Inhaled Corticosteroids - Adverse Effects

A

Immunosuppression - oral candidiasis - need to rinse mouth after use
Hoarse voice in COPD
High dose - release into systemic - adrenal suppression, growth retardation and osteoporosis

67
Q

Inhaled Corticosteroids - Warnings

A

Cautioned at a high - dose in patients with a history of pneumonia and in children at risk of growth suppression

68
Q

Leukotriene receptor antagonist - Montelukast - Indications

A

Adults: Add on if not controlled well by inhaled corticosteroids and LABAs
Children 5-12: alternative to LABAs where inhaled corticosteroids are insufficient
Children under 5 years: 1st line preventative therapy in young children with asthma who cannot take steroids

69
Q

Leukotriene receptor antagonist - Montelukast - Mechanism of Action

A

Blocking the CysLT1 receptor and damping down the inflammatory cascade

70
Q

Leukotriene receptor antagonist - Montelukast - Adverse Effects

A

Usually well-tolerated
Mild Headache and abdominal pain
Increased rate of URTIs
Rare- hyperactivity

71
Q

Leukotriene receptor antagonist - Montelukast - Warnings

A

Not prescribed unless incompletely controlled with inhaled corticosteroids and LABAs

72
Q

Adrenaline - Indications

A

Cardiac Arrest - Advanced Life Support - treatment algorithm for shockable and non-shockable rhythms
Anaphylaxis
Injected directly into tissues to induce local vasoconstriction - used in endoscopy to control mucosal bleeding - sometimes mixed with local anaesthetic to control mucosal bleeding - sometimes mixed with local anaesthetic drugs (e.g. lidocaine) to prolong local anaesthetic

73
Q

Adrenaline - Adverse Effects

A

Restoration os cardiac output - followed by adrenaline -induced hypertension
When given to conscious patients in anaphylaxis or in an attempt to produce local vasoconstriction - often causes anxiety, tremor, headache and palpitations
Patients with existing heart problems - angina, MI and arrhythmias

74
Q

Adrenaline - Warnings

A

None in cardiac arrest or anaphylaxis
For local vasoconstriction - should be given with caution in patients with heart disease
Adrenaline - anaesthetic preparations should not be given in areas supplied by an end-artery - fingers and toes - can cause tissue necrosis

75
Q

Adrenaline - Interactions

A

In patients on beta-blockers - may induce widespread vasoconstriction

76
Q

Adrenaline - Warnings

A

None in cardiac arrest or anaphylaxis
For local vasoconstriction - should be given with caution in patients with heart disease
Adrenaline - anaesthetic preparations should not be given in areas supplied by an end-artery - fingers and toes - can cause tissue necrosis

77
Q

Anti-histamine - Indications

A

Allergy
Relief pruritis and hives (urticaria) due to insect bites, infections and drug allergies
Adjunct treatment in anaphylaxis after administration of adrenaline
Other class used in nausea and vomiting

78
Q

Anti- histamine - Adverse Effects

A

1st generation antihistamine (e.g. chlorophenamine) cause sedation - histamine has a role in wakefulness
2nd generation antihistamine (e.g. loratadine, cetirizine and fexofenadine) do not cross the blood - brain barrier - have fewer adverse effects

79
Q

Anti-histamine - Warnings

A

Mainly safe

Cautioned in patients with severe liver disease - may precipitate hepatic encephalopathy

80
Q

Adenosine - Indications

A

As a first line diagnostic and therapeutic agent in supraventricular tachycardia (SVT), usually evident on the ECG as a regular, narrow - complex tachycardia

81
Q

Adenosine - Mechanisms of Action

A

Adenosine is an agonist of adenosine receptors on cell surfaces.
In the heart, activation of these G-protein coupled receptors induces severe effects, including reducing the frequency of spontaneous depolarisation (automacity) and increasing resistance to depolarisation (refractoriness)
In turn, this transiently slows the sinus rate and conduction velocity and increases the AV node refractoriness.
Many forms of SVT arise from a self-perpetuating electrical (re-entry) circuit that takes in the AV node
Increasing refractoriness in the AV node breaks the re-entry circuit, which allows normal depolarisations from the sinoatrial (SA) node to resume control of heart rate (cardioversion).
Where the circuit does not involve the AV node (e.g. in atrial flutter), adenosine will not induce cardioversion.
However by blocking conduction to the ventricles, it allows closer inspection of the atrial rhythm on the ECG
This may reveal the diagnosis
The duration of effect of adenosine is very short because it is rapidly taken up by cells (e.g. red cells)
Its half-life in plasma is less than 10 seconds

82
Q

Adenosine - Adverse Effects

A

Can induce bradycardia and even asystole
Deeply unpleasant sensation for the patient
Sinking feeling in the chest - accompanied by breathlessness and a ‘sense of impending doom’
Usually short-lived

83
Q

Adenosine - Warnings

A

Should not be administered to patients that cannot tolerate its transient bradycardic effects e.g. those with hypotension, coronary ischaemia, decompensated heart failure
Adenosine may induce bronchospasm in susceptible individuals so should be avoided in patients with asthma or COPD
Patients who have had a heart transplant are very sensitive to the effects of adenosine

84
Q

Adenosine - Interactions

A

Dipyridamole, an antiplatelet agent, blocks cellular uptake of adenosine.
This prolongs and potentiates its effect, so the dose of adenosine should be halved.
Theophylline and aminophylline (systemic bronchodilators) are competitive antagonists of adenosine receptors and reduce its effect.
Patients who have taken these drugs respond poorly and may require higher doses

85
Q

Amiodarone - Indications

A

Used to treat a wide range of tachyarrhthymias, including atrial fibrillation (AF), atrial flutter, supraventricular tachycardia (SVT), ventricular tachycardia (VT).
Used when other therapeutic options (drugs or electrical cardioversion) are ineffective or inappropriate

86
Q

Amiodarone - Mechanism of Action

A

Has many effects on myocardial cells, including blockade of sodium, calcium and potassium channels and antagonism of alpha and beta - adrenergic receptors.
There effects reduce spontaneous depolarisation (automaticity), slow conduction velocity and increase resistance to depolarisation (refractoriness), including in the AV node.
By interfering with AV node conduction, amiodarone reduces the ventricular rate in AF and atrial flutter.
Through its other effects it may also increase the chance of conversion to and maintenance of sinus rhythm.
In SVT involving a self-perpetuating (‘re-entry’) circuit that includes the AV node, amiodarone may break the circuit and restore sinus rhythm.
Amiodarone’s effects in suppressing spontaneous depolarisations make it an option for both treatment and prevention of VT and for improving the chance of successful defibrillation in refractory VF.

87
Q

Amiodarone - Adverse Effects

A

In acute use, compared with other anti-arrhythmic drugs, amiodarone causes relatively little myocardial depression.
It can cause hypotension during IV infusion, although this is probably an effect of the solvent with which it is formulated, rather than the drug itself.
When taken chronically, amiodarone has many side effects, several of which are serious.
These include effects on the lungs (pneumonitis), heart (bradycardia, AV block), liver (hepatitis) and skin (photosensitivity and grey discolouration).
Due to its iodine content (amIODarone) and structural similarities to thyroid hormone, it may cause thyroid abnormalities, including hypo- and hyperthyroidism.
Amiodarone has an extremely long half-life.
After discontinuation, it may take months to be completely eliminated

88
Q

Amiodarone - Warnings

A

Amiodarone is a potentially dangerous drug that should be used only when the risk-benefit balance justifies this.
It should generally be avoided in patients with increased severe hypotension, increased heart block, and increased active thyroid disease.

89
Q

Amiodarone - Interactions

A

Amiodarone interacts with many drugs.
Increases the plasma concentrations of digoxin, diltiazem and verapamil.
This may increase the risk of bradycardia, AV block and heart failure.
The doses of these drugs should be halved if amiodarone is started

Clinical Pharmacology and Prescribing (1 decks)

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