Pharmacology of Arthritis Flashcards
3 steps of pain management?
Step 1: Non-opioid e.g. aspirin, paracetamol or NSAID
Step 2: Weak opioid for mild to moderate pain e.g. codeine
Step 3: Strong opioid for bad pain .e.g morphine
2 actions of NSAIDs? Some examples?
Anti-inflammatory and analgesic Examples: • Ibuprofen • Naproxen • Diclofenac • Indometacin • Etodolac • Celecoxib (Cox 2 inhibitor)
Indications for NSAIDs?
Inflammatory arthritis, mechanical MSK pain, pleuritic/ pericardial pain.
Adverse effects of NSAIDs?
- Dyspepsia
- Oesophagitis
- Gastritis
- Peptic Ulcer
- Small/large bowel ulceration
- Renal impairment
- Increased cardiovascular events (Cox 2 inhibitors + others)
- Fluid retention
- Wheeze
- Rash
Describe two routes can take NSAIDs?
Orally
Can also apply topically, this is good for localised pain and reduces adverse affects.
DMARD therapy should be started within _____1______of symptoms starting. Isn’t vital to have antibodies or X-rays before start treatment as may be negative and may be too late.
1) 3 months
Actions of DMARDs? How long do they take to have an affect?
Slow acting - weeks to months
Pure anti-inflammatory with no direct analgesic effect
Reduce rate of disease progression
Why do DMARDs need regular monitoring?
They have lots of adverse side effects
Why is methotrexate given with folate?
As methotrexate is a folate antagonist may become deficient in folate. Folate is involved in new immune cells being produced.
Adverse effects of methotrexate?
- Leucopenia / thrombocytopenia
- Hepatitis / cirrhosis (alcohol intake must be limited)
- Pneumonitis- either you get this or you don’t
- Rash / mouth ulcers
- Nausea / diarrhoea
- Needs monitoring of FBC and LFTs
- Teratogenic. Must be stopped in females at least 3 months before conception. Methotrexate can be replaced with another DMARD during this time.
Woman wants to have a baby on methotrexate what should you do?
Tell them they must stop methotrexate and wait three months before conception METHOTREXATE IS TERATOGENIC
What is often used in combination with methotrexate in early inflammatory arthritis?
Sulfasalazine
What drug is being described:
- Similar efficacy to methotrexate
- Similar side effects
- Also teratogenic
- Very long half life so requires wash out if patient wants to become pregnant
Leflunomide
Hydroxxyquinine uses and side effects?
- No effect on joint damage
- Used in connective tissue disease such as SLE (helps skin, joints and general malaise) Sjogren’s syndrome and RA
Side effects: Retinopathy - recognised but rare effect
What do you need to get a biologic for rheumatoid?
DAS28 of more than 5.1 and already tried two DMARDs at different doses
Examples of Anti TNF therapy? What are they used for?
Licensed for RA, psoriatic arthritis and ankylosing spondylitis. Etanercept, Adalimumab, Certolizumab, Infliximab, Golimumab
Why may everyone not find biologics useful?
Some immune system components have not been discovered to target yet and that may be what is causing the disease.
Adverse effects of biologics?
- Risk of infection (esp TB) significantly higher than DMARDs and need screening for HIV etc even chicken pox and TB.
- Question over risk of malignancy (esp skin cancer)
- Contraindicated in certain situations e.g. pulmonary fibrosis, heart failure
What do you need screened for if going on biologic, why?
TB, HIV, chicken pox etc
Risk of infection is high, if you have latent TB it could become active once you go on the biologic.
Acute treatment of gout?
- Colchicine (diarrhoea common)
- NSAIDs
- Steroids, either oral or IM
When is allopurinol contraindicated?
Renal Impairment
When is febuxostat given?
gout prophylaxis also a xanthine oxidase inhibitor- used when allopurinol can’t be tolerated
4 points to reduce toxicity of corticosteroids?
- Use lowest possible dose for as short a time as possible
- Consider steroid sparing agents
- Osteoporosis prophylaxis
- Watch cardiovascular risk factors
Indications for corticosteroids?
- Connective tissue disease
- Polymyalgia rheumatica / giant cell arteritis
- Vasculitis
- Rheumatoid arthritis
Adverse effects of corticosteroids?
- Weight gain - centripetal obesity
- Muscle wasting
- Skin atrophy
- Osteoporosis
- Diabetes
- Hypertension
- Cataract
- Glaucoma
- Fluid retention
- Adrenal Suppression
- Immunosuppression
- Avascular necrosis of the femoral head
