[ADR] Adverse drug reactions + Interactions Flashcards
TNF-α inhibitors
Reactivation of tuberculosis
Methotrexate (lungs)
Pneumonitis
(also pulmonary fibrosis)
BNF recommends that the patient seeks medical attention if they experience dyspnoea, cough or fever.
Patients who are allergic to aspirin may also react to what?
Sulfasalazine
Main SE of colchicine
diarrhoea
Patients who are allergic to co-trimoxazole may also react to what?
Sulfasalazine
It is a sulfa drug and should be stopped in patients with a documented allergy to other sulfa drug, in this case, it is co-trimoxazole.
What is the treatment for malignant hyperthermia?
May occur secondary to suxamethonium chloride
Dantrolene sodium
Side effects of lithium
Mild lithium toxicity - tremor
Moderate lithium toxicity - lethargy
Severe lithium toxicity - arrhythmias, seizures, coma, and renal failure.
Which drugs can significantly reduce lithium excretion?
Lithium excretion is significantly reduced by ACE-inhibitors, in this case lisinopril, diuretics (and particularly thiazides, in this case bendroflumethiazide), and NSAIDs (not given here).
If a diuretic must be given, loop diuretics (e.g. furosemide) are the safest.
Which antiepileptic causes SIADH?
Carbamazepine
If a patient reacts to co-amoxiclav, which other antibiotic can cause cross-reactivity?
Meropenem (a carbapenem)
What should you do with methotrexate during illness?
STOP taking it
Which antihypertensive can cause facial flushing?
Calcium channel blockers
How do NSAIDs cause AKI?
Through acute interstitial nephritis
NOTE: NSAID-induced nephrotoxicity is more likely to occur in patients with preexisting renal impairment.
Take care when coprescribing NSAIDs and ACE-inhibitors.
Why can co-dydramol cause constipation?
It contains dihydrocodeine (an opioid).
All opioids (including codeine, morphine and, to a lesser extent, tramadol) slow transit through the bowel.
What drugs are considered antimuscarinics?
Cyclizine
Oxybutynin
Tolterodine
What are common side effects of antimuscarinic?
urinary retention, constipation, blurred vision, dry mouth, and GI disturbances
How should vitamin K be given?
By slow IV injection
If no bleeding, by mouth.
Example of Vitamin K drug: Phytomenadione
Which urinary incontinence medications should be avoided in myasthenia gravis?
All antimuscarinics - oxybutynin, tolterodine, solifenacin, trospium
Can give: mirabegron or duloxetine
Signs of diazepam withdrawal
Tremor, anxiety, insomnia
Which diabetes drug(s) are most associated with hypoglucaemia?
insulin and sulphonylureas
Sulphonylureas increase insulin release from the pancreas
Most common side effect of oxybutynin
Dry mouth (anti-muscarinic side effects)
Other common anti-muscarinic side effects include constipation, dizziness, drowsiness, dyspepsia, flushing, headache, nausea, palpitations, skin reactions, tachycardia, urinary disorders, vision disorders and vomiting. The BNF also lists diarrhoea as a general side effect of oxybutynin.
Drugs associated with pancreatitis - FATSHEEP
- Furosemide
- Azathioprine/asparaginase
- Thiazides/tetracyline
- Statins/sulfonamides/sodium valproate
- Hydrochlorothiazide
- (O)Estrogens
- Ethanol
- Protease inhibitors & NRTIs (antiretroviral medications)
Drug class associated with tendon rupture
Fluoroquinolones e.g. ciprofloxacin (often within 48 hours of starting or if combined with corticosteroid)
Major bleeding and an INR above 8
stop warfarin sodium; give phytomenadione (vitamin K1) by slow intravenous injection; give dried prothrombin complex (factors II, VII, IX, and X); if dried prothrombin complex unavailable, fresh frozen plasma can be given but is less effective; recombinant factor VIIa is not recommended for emergency anticoagulation reversal
What are the main adverse effects of hydroxychloroquine on the eye?
Keratopathy and retinopathy
Keratopathy, characterised by corneal deposits can occur after a few weeks of starting treatment. It is completely reversible on withdrawal of treatment and is not usually considered to be a contra-indication to continued treatment. Retinopathy manifests as damage to the photoreceptors and subsequent degeneration of the retinal pigment epithelium. The drug must be stopped but even after stopping the drug, the damage can continue to worsen. Annual monitoring (including fundus autofluorescence and spectral domain optical coherence tomography) is recommended in all patients who have taken hydroxychloroquine for longer than 5 years.
How do penicillin antibiotics affect platelet levels?
Thrombocytopenia is a recognised common side effect of all penicillin antibiotics.
What is a recognised side effect of ticagrelor?
Progressive shortness of breath at rest
What is one of the side effects of folic acid (e.g. when taken during pregnancy)?
flatulence
with appetite loss and abdominal distension being rare but possible adverse effects of the therapy.
Which drugs can lead to worsening of psoriasis?
lithium, beta blockers, antimalarials, NSAIDs and ACE inhibitors
Symptoms of fluoxetine overdose
SEROTONIN SYNDROME
tachycardia, fever, sweating, hyperreflexia, hypertension and agitation, as well as nystagmus
What is a risk factor of benzodiazepine use in the elderly?
associated with decreased alertness, confusion, drowsiness and hypotension, all of which increase the risk of falls
This is particularly important to consider in a patient with Parkinson’s disease, in whom there may already be an element of autonomic instability.
Which anti-diabetic drug can increase the risk of gangrene?
Empagliflozin
This is due to its ability to increase urinary glucose excretion, which in turn raises the risk of urinary and genital infections, including Fournier’s gangrene (a rare bacterial infection that can affect the penis, scrotum, or perineum and tends to worsen over time).
What is the main side effect of pioglitazone?
Weight gain
What is the treatment regime for TB?
Give 4 (RIPE) for 2 months, and then 2 of them for 4 months (depending on Culture and Sensitivity)
* usually P and E stopped due to bigger side-effect profile) (RIP available as combinations Rifater)
* Pyrazinamide and Ethambutol (can bu substituted by Moxifloxacin) - 2 months
- Rifampicin and Isoniazid - 6 months (“Rifinan”)
What are the main side-effects of Rifampacin?
- Enyme inducer
- Orange colouration of secretion
antibiotic that obstructs cell wall synthesis
What are the main side-effects of Isoniazid?
Enzyme inhibitor
peripheral neuropathy
Therefore co-prescribed with: pyridoxine (B6) to prevent this
inhibition of mycolic acid synthesis (part of mycobacteria cell wall)
What is the main side-effect of Pyrazinamide?
Gout
arthralgia
liver toxicity
antimicrobial drug
What is the main side-effect of Ethambutol
Colour blindness (Ishihara test before starting)
antimycobacterial drug that inhibits arabinosyltransferase and thereby stops carbohydrate polymerization of the mycobacterial cell wall
What test should be done before commencing TB treatments?
- HIV test
- Visual acuity testing
- Renal function
- Liver function
Drugs that cause gynaecomastia - DISCO
Digoxin (long-term use)
Isoniazide
Spironolactone
Cimetidine
Oestrogens
Which SSRI is most likely to cause discontinuation syndrome?
Paroxetine (shortest half life)
Symptoms: shock-like sensations, paraesthesia, lethargy, unable to sleep
Diabetic prescribed propranol?
Signs of hypo may be masked (e.g. reduce tremor)
