Chapter 74 Drug Therapy for Gout

Adverse effects of colchicine

GI (severe diarrhea), myelosuppression (bone marrow suppression), and myopathy

Adverse effects of NSAIDs

GI ulceration, decreased renal function, fluid retention, increased risk of cardiovascular events

NSAIDs for acute gouty arthritis

better tolerated and predictable than other drugs for gout, and relief should be felt within 24 hours and swelling should subside within a few days

Goals of drug therapy for hyperuricemia

promote the dissolution of uric crystals, prevent new formation of crystals, prevent disease progression, reduce frequency of acute attacks, and improve quality of life

Colchicine drug interactions

statins, PGP inhibitors, and inhibitors of CYP3A4

Why are drugs for hyperuricemia not good for an acute gouty attack?

they have no analgesic or anti-inflammatory actions

In which patients should glucocorticoids be avoided?

those prone to hyperglycemia or those with diabetes

Colchicine uses

treats an acute gouty attack, reduces incidences of attacks, and aborts an impending attack

Precautions and contraindications for colchicine

older adults, debilitated patients, pts with cardiac, renal, hepatic, and GI disease and pregnant pts

Glucocorticoid used for gout

prednisone

Long term therapy to lower uric acid levels

3 or more attacks a year and urucosuric drugs

A pt is prescribed allopurinol for chronic tophaceous gout. The pt develops a rash. What is the priority intervention by the nurse? A. stop the medication and assess the pt for liver and kidney failure B. instruct the pt to avoid exposing the skin to sunlight C. administer diphenhydramine with one dose of allopurinol D. monitor the pt for respiratory depression

A. Rationale: A serious toxic reaction to allopurinol is hypersensitivity syndrome. The medication should be immediately discontinued; the pt should be observed for rash, fever, eospinophelia, and liver and kidney dysfunction

The nurse teaches a patient with gout that naproxen [Naprosyn] is an agent of first choice for treatment over colchicine. The nurse should use which rationale for the teaching? A. Naproxen achieves more predicable pain relief with fewer side effects. B. Treatment with naproxen must continue over a long period to restore joint function. C. Naproxen causes less impairment of carbohydrate metabolism and less risk of hyperglycemia. D. Naproxen reduces uric acid levels sooner and with less risk to the kidneys.

A. Rationale: Naproxen is a nonsteroidal anti-inflammatory drug (NSAID) that is used to suppress inflammation in gout. Compared with colchicine, NSAIDs are better tolerated and have more predictable effects. Because safe, effective alternatives are available, the use of colchicine has declined. The treatment time with NSAIDs is brief, because pain relief occurs within 24 hours and swelling subsides over a few days. Hyperglycemia is more of a concern when glucocorticoids are used. NSAIDs do not affect uric acid levels.

When evaluating the effects of probenecid, the nurse should monitor which laboratory result? A. Uric acid level B. Sodium level C. Hemoglobin D. Blood pH

A. uric acid level Rationale: Probenecid acts on the renal tubules to increase uric acid excretion, and plasma urate levels are reduced as a result. The sodium level, hemoglobin, and blood pH are not affected by probenecid.

A nurse is teaching a patient with chronic tophaceous gout who is scheduled to start taking allopurinol [Zyloprim]. Which of these statements should the nurse include in the teaching? A. "You'll see the joint swelling reduced in your toe in just a few days." B. "You may notice an increase in your pain attacks in the first month." C. "We need to collect periodic hair samples to measure uric acid levels." D. "It'll be important to minimize fluid intake so the kidneys can rest."

B. Rationale: Allopurinol inhibits xanthine oxidase to reduce uric acid levels in chronic tophaceous gout. During the first months of treatment, it may increase the incidence of acute gouty arthritis. Allopurinol lacks anti-inflammatory and analgesic actions and is not useful in an acute gout attack. Plasma levels of uric acid are evaluated. To prevent renal injury, fluid intake should be increased.

When planning interventions for pain control in a patient with gouty arthritis, the nurse should assess for pain in which joints? A. Hands B. Feet C. Shoulders D. Neck

B. feet Rationale: Gout is characterized by hyperuricemia and episodic pain attacks from urate crystals, which are deposited most commonly in the great toe. The kidneys also can be damaged. When gout is chronic, tophi, or large, gritty deposits, may form in the affected joint. Joints in the hands, shoulders, and neck are not commonly affected by gout.

A nurse obtains a health history from a patient who has gout and is taking a glucocorticoid. The nurse should follow up on which finding? A. Flushing and urticaria B. Heart rate of 88 beats/min C. Blood glucose level of 140 mg/dL D. 6-kg weight loss

C. Rationale: Glucocorticoids are very effective in the treatment of acute gout attacks and are preferred for patients who are not candidates for or are unresponsive to NSAIDs. Because of their effects on carbohydrate metabolism, glucocorticoids should be avoided in patients prone to hyperglycemia. Flushing and urticaria are not associated with glucocorticoid use. The heart rate is not affected by glucocorticoids. Glucocorticoids cause weight gain, not weight loss.

The nurse should be concerned about which finding in a patient on long-term, low-dose colchicine therapy to prevent gout? A. White blood cell (WBC) count of 6500/mcL B. Platelet count of 200,000/mcL C. Complaints of muscle pain and weakness D. Complains of headache

C. Rationale: Long-term, low-dose therapy with colchicine can cause rhabdomyolysis, which is manifested by complaints of muscle tenderness, pain, and weakness. Because the drug causes myelosuppression, patients should be monitored for leukopenia and thrombocytopenia. Both the WBC count and platelet count are within normal limits. Headache is not an adverse effect of colchicine.

A pt with acute gouty arthritis requests information on the preferred drug to take to treat a painful flare-up. The nurse should recommend which medication? A. allopurinol B. febuxostat C. probenecid D. naproxen

D. Rationale: NSAIDs and glucocorticoids are preferred drugs for treating acute gouty attack. The other drugs are used long term to prevent gouty attacks.

Drugs used short term to relieve symptoms of an attack

NSAIDs are the first line and glucocorticoids are also used

2 drugs that inhibit uric acid formation

allopurinol and febuxostat

Probenecid drug interactions

aspirin and other salicylates

Gout

characterized by high levels of uric acid and a buildup of uric acid crystals in the joint that leads to episodes of severe joint pain (typically in large toe)

Uses of febuxostat (Uloric)

chronic tophaceous gout

Uses of allopurinol

chronic tophaceous gout and hyperuricemia due to chemotherapy

Which drug for gout can prevent an attack from occurring?

colchicine

Pegloticase MOA

converts uric acid to allatonin which is a compound that is readily excreted by the kidneys (allows joint function to improve, decreases risk of nephropathy)

Is colchicine used for other anti-inflammatory disorders?

no, only used for an acute gouty attack

Causes of gout

excessive production of uric acid or impaired renal excretion of uric acid

Infrequent flare-ups of gout are categorized as...

fewer than 3 attacks per year

Glucocorticoids uses for gout

helps with the pain and decreases inflammation (helpful for those who cannot take NSAIDs)

Adverse effects of allopurinol

hypersensitivity reactions, GI effects, and neurologic effects, initial therapy can elicit an acute gouty attack (generally well tolerated)

Other uses of allopurinol

hyperuricemia due to chemotherapy and certain blood dycrasias like polycythemia Vera, myeloid metaplasia, and leukemia

probenacid MOA

increases uric acid excretion

Other NSAIDs that can be used

indomethacin (Indocic)

Hyperuricemia can also cause

kidney stones (crystals that build up in the kidneys because of excess uric acid)

Adverse effects of febuxostat (Uloric)

liver function abnormalities, nausea, arthralgia, and rash

Gout is seen mainly in..

men

Adverse effects of probenecid

mild GI effects (take with food) and risk fo kidney damage that can be prevented by drinking fluid the first few days of treatment