Linger Rheumatic Pharm Flashcards
Basic Principles of RA Treatment
Early and aggressive use of DMARDs for all patients
Tight control is important
- Goal should be remission or low disease activity
- Frequent reassessment of response
- Monitoring and prevention of drug toxicity
Response time
- Nonbiologic DMARDs are slower (1-6 months)
- Biologic DMARDs are faster (1-2 weeks); some patients report improvement after the first dose
Use of NSAIDs and glucocorticoids as adjunct therapy
- To control symptoms during initial DMARD treatment, regimen modification, or disease flares
- Provide immediate pain relief
Standard Approach for Pharmacologic Treatment of RA
- DMARD + NSAID ± corticosteroid
- Methotrexate (MTX) is used in 50-70% of cases
- Hydroxychloroquine (HCQ) or sulfasalazine (SSZ) are safer alternatives for mild disease
- If response is inadequate, second or third DMARD can be added - TNF-α inhibitor (monotherapy or with nonbiologic DMARD)
- More effective and faster response than nonbiologic DMARDs
- Second-line due to long-term adverse effects (1st line after inadequate response to nonbiologics) - Switch to a different TNF-α inhibitor or a non-TNF biologic
- Patients who do not respond to one TNF inhibitor may respond to another TNF inhibitor or a non-TNF inhibitor
- Currently no evidence that any one TNF inhibitor is more effective than any other
Combination DMARD Therapy
Combinations of 2 or even 3 DMARDs are often used
- Complementary mechanisms of action
- Non-overlapping pharmacokinetics
- Non-overlapping toxicities
Most combinations are methotrexate-based
Combinations of two drugs can include MTX and another nonbiologic DMARD or MTX and a biologic DMARD
Triple therapy: MTX + HCQ + SSZ
Combining different biologic DMARDs is not recommended
- Increases risk of infection without significant benefit
Treatment of Acute Gout
NSAIDs
- First-line therapy for acute gout
- MOA: inhibit urate crystal phagocytosis and PG synthesis
- Common choices: indomethacin, naproxen, sulindac, celecoxib
- Aspirin, salicylates, and tolmetin are not used
Colchicine
- Formerly primary therapy; now rarely used due to toxicity
- Can be used in patients with NSAID contraindications
Glucocorticoids
- Sometimes used for severe gout
- Administered intraarticularly, orally, or parenterally depending on the number of joints involved
Prevention of Recurrent Gout
Antihyperuricemic (urate-lowering) therapy
- Xanthine Oxidase Inhibitors
- — Decrease urate synthesis
- — Allopurinol and febuxostat
- Uricosuric Agents
- — Enhance renal excretion of uric acid
- — Probenecid (antihypertensive losartan has uricosuric effects)
Anti-inflammatory drugs (NSAIDs or colchicine)
- Used early in urate-lowering therapy when mobilization of uric acid is associated with a temporary increase in the risk of acute gout
Gout- where it comes from
Gout results from precipitation of urate crystals in the tissues
An inflammatory response is caused by phagocytosis of urate crystals
Hyperuricemia is a prerequisite, but does not always result in gout
how gout drugs work
Synoviocytes phagocytose urate crystals and then secrete inflammatory mediators, which attract and activate polymorphonuclear leukocytes (PMN) and mononuclear phagocytes (MNP) (macrophages). Drugs active in gout inhibit crystal phagocytosis and polymorphonuclear leukocyte and macrophage release of inflammatory mediators. PG, prostaglandin; IL-1, interleukin-1; LTB4, leukotriene B4.
Lady has morning stiffness, fatigue, body aches, weight loss, sweeling, tenderness and warmth in the MCP and PIP joints.
Joint erosions
High RF
Anti CCP antibody
What’s she got?
rheumatoid arthritis
Lady has RA and we start her on methotrexate. What’s the main purpose of that?
Slow, stop, and possibly reverse joint pathology in RA
Disease-Modifying Antirheumatic Drugs = DMARDs
Which of the following adverse effects is most likely following administration of MTX for RA?
Myelosuppression Nephrotoxicity Ocular toxicity Stomatitis Viral infection
Stomatitis
in doses for cancer you’d have nephrotoxicity and myelosuppression too, but not here for RA as much
Methotrexate (MTX)
Doses used in rheumatic diseases are much lower than those used for cancer
- Different primary mechanism of action (MOA)
- Reduced toxicity compared to use in cancer chemotherapy
Response time: 4-6 weeks or longer
Clinical Uses
- First-line DMARD for RA; used in 50%-70% of cases
- Psoriasis; unlabeled use in Crohn’s diseases
- Used at much higher doses in many cancer chemotherapy regimens (inhibits dihydrofolate reductase)
Methotrexate Adverse Effects
Common side effects
- Nausea, upset stomach, loose stools
- Stomatitis or soreness of the mouth
- Alopecia
- Fever
- Macular punctate rash (usually on the extremities)
- Headache, fatigue, or impaired ability to concentrate
Hepatic enzymes are frequently elevated, but cirrhosis is rare (< 1%)
Myelosuppression and nephrotoxicity are much less frequent with low-dose therapy than high-dose MTX
Lung damage may be due to inflammation, infection, or MTX-related neoplasia
Contraindicated in pregnancy (teratogenic)
Which of the following agent(s) may be used to reduce the side effects of methotrexate?
Calcium Folic acid Folinic acid Pyridoxine Vitamin C
Folic acid- cheap Folinic acid (leucovorin)- expensive (rescue from high dose)
Pyridoxine is vitamin B6- anti-emetic effects for morning sickness, helps against isoniazid induced peripheral neuropathy.
The patient’s multidrug regimen also includes an agent that will provide immediate pain relief due to its analgesic and anti-inflammatory effects. Which drug best meets this description?
Acetaminophen Hydroxychloroquine Ibuprofen Oxycodone Sulfasalazine
Ibuprofen
Acetominophen is just analgesic but NOT anti-inflammatory
hydroxychloroquine is a DMARD, not imediate effect
Oxycodone- opiate agonist, analgesic but not anti-inflammatory
Sulfasalazine- DMARD
Role of NSAIDs in Treatment of RA
NSAIDs have immediate analgesic and anti-inflammatory effects, but usually do not affect disease progression
Typically used during DMARD induction, during transition to a different DMARD, or during disease flares
Some commonly used agents: ibuprofen, naproxen, diclofenac
Aspirin is not typically used due to GI toxicity; COX-2-selective celecoxib exhibits less GI irritation
No oral NSAID is consistently more effective than any other for treatment of RA; choice based on efficacy/toxicity (varies by patient)