Adverse Effects and Interactions

Question 1

Adverse Effects

Drugs Causing Toxic Acute Tubular Necrosis

Answer 1

• aminoglycosides
• cisplatin
• ethylene glycol (antifreeze)

Question 2

Adverse Effects

Drugs Causing Acute Confusion

Answer 2

• Morphine
• metoclopramide
• benzos
• anticholinergics
• anticonvulsants
• parkinson’s meds
• steroids
• intoxication - alcohol, drugs
• carbon monoxide
• heavy metals
• withdrawal - barbiturates, alcohol, opiates, deficiency of thiamine, nicotinic acid or B12

Question 3

Adverse Effects

Drugs Causing Pulmonary Fibrosis

Answer 3

• amiodarone
• bleomycin
• busulfan
• nitrofurantoin
• methotrexate
• gold
• penicillamine
• illicit drugs - crack cocaine, heroin

Question 4

Adverse Effects

Drugs Causing Low Potassium

Answer 4

• potassium wasting diuretics: thiazides, frusemide
• laxatives
• beta adrenergics (salbutamol),
• theophylline
• corticosteroids and fludrocortisone
• penicillins, aminoglycosides,
• amphotericin B
• insulin
• pseudoephidrine
• verapamil OD

Question 5

Adverse Effects

Drugs Causing Acute Pancreatitis

Answer 5

• thiazides, frusemide
• azathioprine
• tetracyclines
• valproate
• oestrogens, OCP
• corticosteroids
• sulphonamides

Question 6

Adverse Effects

Drugs Causing Low Sodium

Answer 6

• carbamazepine, lithium
• haloperidol, fluphenazine
• SSRIs, tricyclics
• MDMA
• tramadol
• vincristine
• desmopressin
• fluphenazine

Question 7

Adverse Effects

Drugs Causing High Potassium

Answer 7

• potassium-sparing diuretics: amiloride, spiro
• ACE inhibitors, ARBs
• NSAIDs
• ciclosporin, tacrolimus
• pentamidine (for PCP pneumonia)
• co-trimoxazole
• ketoconazole
• metyrapone (cortisol blocker)

Question 8

Adverse Effects

Drugs Causing Urinary Retention

Answer 8

• aminoglycosides - gentamicin
• chemo - cisplatin, carboplatin

Question 9

Adverse Effects

Drugs Causing Urinary Retention

Answer 9

• opioids
• anticholinergics
  
  • antipsychotics
  • antidepressants
  • respiratory (ipratropium)
  • detrusor relaxants
• GA
• alpha agonists
• benzodiazepines (diazepam)
• NSAIDs
• CCB
• antihistamines
• alcohol

Question 10

Adverse Effects

Drugs Causing Temporary Ototoxicity

Answer 10

• salicylates
• quinines
• loop diuretics

Question 11

Hepatic Enzyme Inducers

Answer 11

INDUCERS = hepatic enzyme is more active, so it BREAKS things DOWN

therefore other meds/chemicals/effects are decreased

B = Barbituates
R = Rifampicin
E = Epilepsy = carbemazepine, phenytoin
A = Athlete’s foot = griseofulvin
K = K-sparing diuretic = spironolactone
S = Smoking

DOWN = Drinking Over What’s Normal (chronic alcohol use)

Question 12

Hepatic Enzyme Inhibitors

Answer 12

INHIBITORS = hepatic enzymes are less active

therefore other meds/chemicals are in the blood longer - enzyme inhibitors KEEP DRUG ACTIVE.

K = ketoconazole and fluconazole
E = erythromycin
E = ethanol (acute)
P = PPIs and antacids = omeprazole, cimetidine

D = depression = fluoxetine and sertraline
R = ritonavir
U = sUlphonamides
G = gout = allopurinol

A = amiodarone
C = ciprofloxacin
T = too much grapefruit
I = isoniazid
V = valproate
E = eye drops = chloramphenicol

Question 13

Avoid in Heart Failure

Answer 13

Fluid retention

• pioglitazone (fluid retention)
• NSAIDs (except low-dose aspirin)
• glucocorticoids

Negative inotropy

• verapamil
• flecanide (class I anti arrhythmics)

Question 14

Alendronic Acid

Counselling Points

Answer 14

• swallow whole with plenty of water
• sit upright during and for 30mins after
• take on an empty stomach
• 30mins before further oral intake

Question 15

Digoxin

Interactions

Answer 15

decreased renal clearance combined with:

• amiodarone
• verapamil
• propafenone
• captopril

increased absorption with erythromycin

Question 16

Digoxin

Signs of Toxicity

Answer 16

• heart block
• atrial tachycardia
• ventricular arrhythmias
• xanthopsia

Question 17

Statins

Side Effects

Answer 17

• myalgia (common)
  
  • myopathy, myositis, rhadbomyolysis (rare)
• deranged LFTs
  
  • don’t reduce or stop dose unless LFTs 3x normal limit
• GI disturbance
• sleep disturbance
• headache

Question 18

Things to consider giving when prescribing steroids

Answer 18

• PPI (ulcers)
• medic alert bracelet/card
• higher doses during stress (infection, surgery)
• calcium, vitamin D, bisphosphonates (osteoporosis)

Question 19

Steroids

Avoid giving these things

Answer 19

• NSAIDs (ulcer risk)
• live vaccines within 3 months

Question 20

Steroids

Patients to monitor carefully

Answer 20

• Diabetics - for worsening sugars
• glaucoma - for worsening pressures
• CCF for fluid retention

Question 21

Steroids

How to withdraw

Answer 21

if prescribing for more than 3 weeks, reduce gradually

Question 22

Steroids

(Oral)

Side Effects

Answer 22

• hypertension and CCF
• osteoporosis
• peptic ulcers and GORD
• diabetes
• psych: depression, anxiety, confusion, psychosis, irritability, mood swings
• appearance: thin skin, cushingoid facies (moon face), straie, intrascapular fat pad, acne, bruising
• eyes: glaucoma, cataracts
• decreased immune function - delayed wound healing

Question 23

Monitoring

Allopurinol

Answer 23

serum urate

Question 24

Monitoring

ACEi

Answer 24

renal function

Question 25

Beta Blockers

Contraindications

Answer 25

• bronchospasm, asthma
• heart failure
• heart rate < 50bpm
• 2nd or 3rd degree heart block
• cardiogenic shock
• allergy (to BB)