pharmacology Flashcards
side effects of vincristine
abdo pain, constipation, neuropathy
side effects of cyclophosphamide
Cyclophosphamide can cause urothelial mucosal toxicity. ie haemorhagic cystitis
side effects of cyclophosphamide
Cyclophosphamide can cause urothelial mucosal toxicity. ie haemorhagic cystitis
SIde effects of doxorubicin
Anthracyclines can cause cardiotoxicity and assessment of cardiac function with echocardiography is important prior to using this class of drug.
Side effects of rituximab
Rituximab is a monoclonal antibody to CD20 which is usually associated with infusional toxicity such as hypotension and may cause delayed neutropenia.
side effects of bleomycin
Bleomycin related pulmonary fibrosis
chronic lead poisoning
Chronic lead poisoning gives rise to a peripheral motor neuropathy as a result of demyelination. Effects on the central nervous system lead to headaches, lethargy and mood and behaviour disorders.
The effects of lead on gastrointestinal smooth muscle cells lead to colicky abdominal pain, constipation and anorexia.
Lead poisoning gives rise to iron deficiency anaemia with a blood film demonstrating classical features of iron deficiency. Basophilic stippling is seen in red blood cells as multiple small dots seen in the cell cytoplasm. It is always pathological and represents toxic injury to the bone marrow. Lead poisoning is a well-recognised cause of this phenomenon.
Although lead poisoning is far more commonly seen in children than adults this patient’s learning difficulties may put him at risk. He may have been ingesting lead in the form lead-based paint dust or chippings - the concentration of lead rose to its highest concentration in 1955 and as a result many post-war houses have a significant concentration of lead in their original paintwork. Lead-based paints (except for specialist uses) have been banned in the UK since 1992.
Chornic arsenic poisoning
Chronic arsenic poisoning typically presents with features of:
Diabetes
Skin changes (hypopigmentation, hyperkeratosis)
Sensory-motor neuropathy, and
Cancers (lung, bladder, skin).
mercury poisoning
Mercury poisoning gives rise to nausea, persistent metallic taste, gingivostomatitis, tremor and nephrotic syndrome.
TCA OD
Tricyclic antidepressants are recognised to lead to QT prolongation and myocardial depression, and loading with sodium bicarbonate reverses these effects.
sedating antihistamines
Sedation and headaches are the most common adverse effects of antihistamines. First generation antihistamines (chlorpheriramine and diphenhydramine) are more sedating than the newer agents. Of the newer antihistamines, cetirizine and levocetirizine are more sedating than loratadine and desloratadine, and possibly more sedating than fexofenadine.
cyanide poisoning mechanism
Cyanide causes the inhibition of the enzyme cytochrome oxidase c which is an essential part of the mitochondrial electron transfer chain (ETC). It therefore interferes with the basic process of cellular respiration, preventing the formation of ATP and causing rapid cell death.
NSAIDS
A non-steroidal anti-inflammatory drug (NSAID) would seem a good treatment for this gentleman’s bone pain but the choice is a difficult one given his history of ischaemic heart disease.
Cyclo-oxygenase-2 (COX2) selective inhibitors (for example, celecoxib and rofecoxib) are associated with an increased risk of thrombotic events (for example, myocardial infarction and stroke) and are rarely used in preference to non-selective agents. COX2 selective inhibitors are, however, associated with a lower risk of serious upper GI side effects and can be a good choice for those with a high risk of ulceration or bleeding.
Some non-selective NSAIDs are also associated with an elevated thrombotic risk, including diclofenac 150 mg daily and ibuprofen 2.4 g daily, therefore these are also the incorrect choices in this case.
Naproxen (1 g daily) is associated with a lower thrombotic risk which makes it the correct answer in this case. Low dose ibuprofen (1.2 g daily) would also be a relatively safe choice for this patient as it has not been linked to an increased risk of myocardial infarction.
Other considerations when prescribing NSAIDs are that they should be avoided in renal failure and used with caution in the elderly. All NSAIDs are contraindicated in severe cardiac failure and in those patients with a history of hypersensitivity to aspirin. They should be used with caution in those patients with coagulation defects and it is worth noting that long term use of NSAIDs can lead to impaired female fertility (reversible on withdrawal of the drug).
SEs of opiods
side effects of opioid medication including nausea and constipation (not diarrhoea).
The rarer symptoms of neurotoxicity (for example, hallucinations, myoclonus and delirium) and respiratory depression are the cause of much anxiety amongst prescribers.
