Arthritic Disorders Flashcards
Drug treatment for osteoarthritis is…
mostly symptomatic.
Relieve pain or inflammation.
List examples of pain relief/anti-inflammatory drugs used for osteoarthritis.
Pain relief/anti-inflammatory
- Paracetamol
- Non-selective NSAIDs (e.g. meloxicam)
- COX-2 inhibitor (e.g. celecoxib)
- Corticosteroids
If the above drugs do not work, move to symptomatic slow-acting drugs for OA (SYSADOA).
List examples of SYSADOA drugs used for osteoarthritis.
- Intra-articular hyaluronic acid: hyaluronic acid naturally exists in synovial fluid. It is a large glycosaminoglycan that works for shock absorption, traumatic energy dissipation, protective coating of cartilage, lubrication & reducing of pain and stiffness. Ultimately, it induces body’s biosynthesis of hyaluronic acid and extracellular matrix
- Chrondroitin sulphate (oral/intra-articular injection)
- Glucosamine
What are the goals of gouty arthritis drug treatment?
- Relieve acute gouty attack
2. Prevent recurrent gouty episodes
What are examples of drugs used to relieve acute gouty attacks?
- NSAIDs (e.g. naproxen)
- COX-2 inhibitors (e.g. celecoxib)
- Glucocorticoids (e.g. prednisolone)
- Colchicine
What are examples of drugs used to relieve prevent gouty episodes?
Intention is to lower uric acid in body!
- Xanthine oxidase inhibitors (e.g. allopurinol)
- Uricosuric agents (e.g. probenecid)
MOA of colchicine?
Used for gout treatment - relieves pain and inflammation in an acute gouty attack within 24-36h.
- Binds to tubulin
- Prevents tubulin polymerisation into microtubules
- Inhibits leukocute migration and phagocytosis
- Inhibits leukotriene B4 and PG production
Side effects of colchicine?
Diarrhoea
Nausea/vomiting
Abdominal pain
Unusual bleeding
Pale lips
Muscle weakness
Change in urine amount
MOA of xanthine oxidase inhibitors?
e.g. allopurinol
- Allopurinol is a purine analog
- Binds to XO and inhibits it
- Decrease metabolism of hypoxanthine to xanthine to uric acid
- Acts as a anti-hyperuricemic agent
Xanthine oxidase inhibitors can be used for…
- Debilitating gout attacks
- Chronic erosive arthritis
- Urate nephrolithiasis
Contraindications for xanthine oxidase inhibitors?
Allopurinol hypersensitivity syndrome (AHS), manifesting as SJS (common in Asians).
Risk factors:
- Renally impaired (increased risk of AHS)
- Thiazide therapy (induces hyperuricemia)
- HLA-B58 antigen (causes SJS/TEN with allopurinol)
Side effects of xanthine oxidase inhibitors?
Jaundice
Dark urine
Skin rash
Nausea, vomiting
Diarrhoea
Stomach pain
Fever
Sore throat
MOA of uricosuric agents?
e.g. probenecid
- They are organic acids
- Will inhibit anion transport sites at the proximal tubule, which inhibits uric acid reabsorption (and increases its excretion)
- Use it when XO inhibitors are contraindicated
Precautions for use of uricosuric agents (probenecid)?
- Take a lot of fluid to minimise renal stone formation
2. Keep urine at pH >6 by administering alkaline substances e.g. potassium citrate
Side effects of uricosuric agents (probenecid)?
Nausea, vomiting
Painful urination
Lower back pain
Allergic reactions
Rash