Musculoskeletal System Flashcards
Give 5 examples of NSAIDs
- Celecoxib
- Diclofenac
- Etoricoxib
- Ibuprofen
(* Aspirin at low dose)
Order the NSAIDs in order of COX-1 selectivity to COX-2 selectivity.
Aspirin (low dose), ibuprofen, naproxen, diclofenac, celecoxib, etoricoxib
What happens when you inhibit COX enzymes?
Reduce prostaglandin, prostacyclin and thromboxane synthesis
How are NSAIDS useful as analgesics?
Less prostaglandin synthesis, less NT release, so less excitability of neurones in pain relay pathway
How are NSAIDs useful as anti-inflammatory agents?
Reduced prostaglandin production at site of injury, so reduced vasodilation and oedema - symptomatic relief
How are NSAIDs useful as antipyretics?
Prostaglandin usually stimulates pyrogens (cytokines) by acting on the thermoregulatory centre of the hypothalamus - so NSAIDs reduce temp
What are the GI considerations of NSAIDs (ADRs and DDIs)?
- Dyspepsia, nausea, peptic ulceration, bleeding and perforation, can make IBD worse
- DDIs - aspirin, glucocorticoid steroids and anticoagulants due to bleeding risks (give with PPI)
Who are NSAIDs contraindicated/cautioned in?
- Elderly
- Prolonged users
- Smokers
- Alcohol drinkers
- Hx of PUD
- H. pylori
What are the renal considerations of NSAIDs (ADRs, DDIs and contraindications)?
- Lead to reversible reduced GFR and renal blood flow, NSAIDs inhibit prostaglandins inhibition of sodium absorption in the CD - so increased sodium absorption
- ACEi, ARBs and diuretics
- Those with CKD or heart failure
What is the advantage of selective COX-2 inhibitors? What is the disadvantage?
Less GI ADRs
No anti platelet action, but inhibit PGI2 so could get unopposed platelet aggregation
What is a consideration that is caused by all NSAIDs?
All NSAIDs increase the risk of MI in low risk people, due to the fine balance between being cytoprotective (prostacyclin) and cytotoxic (thromboxane) on CVS
What are some indications for NSAIDs?
- Inflammatory joint and soft tissue conditions
- Osteoarthritis (topical NSAID or paracetamol tried first though
- Postop pain
- Mennorrhagia
Use lowest effective dose for shortest time necessary, taking into account patient’s risk factors
Give two examples of anticholinesterase drugs.
- Neostigmine
* Pyridostigmine
What drug is methotrexate - what is it used for, what does it do?
- Used in malignancy or RA
* In RA - indirectly suppresses adhesion molecules on T-cells and neutrophils
What are the ADRs for methotrexate?
- Mucositis
- Myelosuppression
^ both get better with folic acid supplements - hepatitis, cirrhosis
- pneumonitis
- increased infection risk
- teratogenic and abortifacient
What drugs are mesalazine and sulfasalazine - what are they used for, what do they do?
- RA (DMARDs)
- 5-ASA donors - anti-inflammatory and fight infection and inhibit T cell proliferation and reduce neutrophil chemotaxis and degranulation
What are the ADRs of sulfasalazine?
- Myelosuppression
- Hepatitis
- Rash
- Nausea and vomiting
- Abdominal pain
Safe in pregnancy
What are infliximab and adalimumab - what are they used for, what do they do?
- RA
* TNF-alpha inhibitors (monoclonal antibodies) - reduce inflammation, angiogenesis and joint destruction
What are the ADRs of TNF-alpha inhibitors?
There is a risk of TB reactivation if the patient has latent TB as TNF-alpha is released by macrophages and maintains granulomas in TB - so screen for latent TB before starting on these drugs
What is Rituximab - what is it used for, what does it do?
- RA
* Causes B cell apoptosis by binding to CD20 B cells
What is hydroxychloroquine - what is it used for, what does it do?
- RA
* A DMARD that increases the pH inside macrophage lysosomes
