Allopurinol is a commonly prescribed medication used to regulate uric acid levels in the body and reduce symptoms associated with gout. As an effective long-term maintenance drug, allopurinol provides numerous health benefits. Still, it can also come with potential risks, necessitating a more thorough understanding of its uses and proper monitoring.
Allopurinol is often considered one of the top 100 most-prescribed medications in the U.S., so it will be on your exams or something you’ll see in the clinical setting.
This blog post will discuss important information on allopurinol, including what it is used for, dosage considerations, drug interactions, and nursing implications.
Table of Contents
Allopurinol Drug Name & Classification
Drug Name
- Generic Name: allopurinol
- Brand Name: Aloprim, Apo-Allopurinol (CAN), Purinol (CAN), Zyloprim
Classification
- Therapeutic: antigout agents, antihyperuricemics
- Pharmacologic: xanthine oxidase inhibitors
Allopurinol Drug Class
Allopurinol is a drug that falls under the class of xanthine oxidase inhibitors. This medication is often used to treat gout and kidney stones. Allopurinol works by decreasing the amount of uric acid produced in the body, which helps reduce the likelihood of developing these health issues.
This medication can effectively reduce the frequency and severity of gout attacks. Still, following the prescribed dosage and talking to your doctor about any potential side effects or interactions with other medications is essential. Understanding the allopurinol drug class can provide valuable insight into how it may help manage certain health conditions.
Medical uses
Gout
Allopurinol reduces urate formation in conditions where urate deposition has already occurred or is predictable. Allopurinol can help prevent and manage gout attacks and protect against tissue damage from uric acid crystals. Reducing uric acid levels in the blood helps reduce symptoms associated with Gout, such as joint pain, inflammation, and swelling.
Tumor Lysis Syndrome Treatment
Allopurinol was a popular treatment for tumor lysis syndrome during chemotherapy, as it can reduce severe hyperuricemia. Nevertheless, this drug has been replaced by urate oxidase therapy over time. In cases where patients cannot take the medication orally, intravenous formulations of allopurinol are used.
Inflammatory Bowel Disease
Co-therapy with allopurinol is being utilized to enhance outcomes for individuals suffering from inflammatory bowel disease and Crohn’s disease who don’t respond well to thiopurine monotherapy. This co-therapy also helps reduce hepatotoxicity that results from treating IBD. The dosage of thiopurine should be reduced significantly, depending on the patient’s thiopurine methyltransferase genetic status.
Psychiatric Disorders
Allopurinol is being tested as an adjunct treatment for mania in bipolar disorder. Meta-analysis has revealed that allopurinol was more efficient than a placebo for managing acute mania (including mixed features). Its effectiveness was unaffected by dosage, follow-up length, or concurrent standard treatment.
Cardiovascular Disease
Studies have suggested that allopurinol may reduce systemic inflammation and improve the risk factors linked to cardiovascular disease. Additionally, a decrease in Oxypurines, generated by xanthine oxidase inhibition, can protect against atherosclerosis development caused by oxidative stress.
Dosage Considerations
ADULTS
- Gout and Hyperuricemia: A daily dose of 100-800 mg orally in divided doses, depending on the severity of the disease (the usual dose is 200-300 mg).
- Maintenance: Establish a dosage that keeps serum uric acid levels within normal boundaries. Prevention from acute gouty attacks: Start with 100 mg orally daily and increase by 100 mg weekly until uric acid levels are below 6 mg/dL.
- Prevention of uric acid nephropathy in certain malignancies: 600-800 mg taken orally for 2-3 days while drinking plenty of fluids; establish a maintenance dose afterward as above.
- Recurrent calcium oxalate stones: 200-300 mg orally daily; adjust dose based on 24-hr urate tests.
- Parenterally: 200-400 mg/m2/day intravenously, up to 600 mg daily as a continuous infusion or every 6, 8, or 12 hours.
PEDIATRIC PATIENTS
- Secondary hyperuricemia associated with various malignancies:
- 6–10 yr: 300 mg/day PO.
- < 6 yr: 150 mg/day; adjust dosage after 48 hr of treatment based on serum uric acid levels.
- Parenteral: 200 mg/m2/day IV as a continuous infusion or at 6-, 8-, and 12-hr intervals.
Routes of Allopurinol
Allopurinol is administered orally and intravenously. Oral doses can be taken with or without food. It is usually diluted in normal saline and infused over 30 minutes when given intravenously. It should not be mixed with other medications or infusion solutions.
Allopurinol Side Effects
Common Side Effects of Allopurinol include
- nausea
- vomiting
- diarrhea
- rash
- drowsiness.
Less Common Side Effects May Include
- headache
- dizziness
- fatigue.
Serious Side Effects May Include
liver or kidney damage or Stevens-Johnson syndrome (a severe skin reaction).
Allopurinol should be taken cautiously by people with pre-existing liver or kidney disease and those who are pregnant or breastfeeding.
Drug Interactions
Allopurinol may interact with certain drugs, including drugs that can increase the risk of bone marrow toxicity, such as
- aminophylline
- azathioprine
- mercaptopurine
- thioguanine and warfarin.
- chlorpropamide;
- cyclosporine;
- cancer medicine;
Additionally, allopurinol may interact with diuretics or medications that affect liver enzymes, such as barbiturates and rifampicin.
Guidelines for Allopurinol Administration
Vital parameters in safe and effective allopurinol administration are:
- Inform your patients that their medication could take a while to break down the uric acid crystals. They may still experience gout attacks, mainly if their levels are high or they’ve had gout for an extended period, even when taking the prescribed medicine.
- Ensure your patients know any possible side effects and when to seek medical help.
- Ensure they understand the importance of maintaining a healthy diet and lifestyle while taking allopurinol, such as avoiding certain foods that contribute to gout (e.g., alcohol, red meat).
- Instruct them to take their dosage on time and as directed.
- Remind them not to take double doses or more of the medication than prescribed, nor mix it with other drugs or supplements without consulting a doctor first.
- Encourage regular follow-up visits so that they can monitor their uric acid levels and adjust the dose as necessary.
- Advise your patients to seek immediate medical help if they experience any alarming side effects, such as chest pain or difficulty breathing.
Allopurinol Nursing considerations
Allopurinol Nursing Assessment:
- Obtain patient history, including allergies, blood dyscrasias, liver disease, renal failure, and lactation.
- Perform a physical exam to evaluate for skin lesions or rash, orientation, and reflexes.
- Order lab tests such as complete blood count (CBC), liver function tests (LFTs), renal function tests, and urinalysis.
Allopurinol Nursing Interventions:
- Administer drugs following meals.
- Encourage the patient to drink 2.5 to 3 L/day of fluids to reduce the incidence of renal stone formation.
- Check urine alkalinity, and consider sodium bicarbonate or potassium citrate to alkalinize the urine if needed.
- WARNING: Discontinue the drug immediately at the first sign of skin rash; severe or fatal reactions may occur.
- Arrange for regular medical follow-ups and blood tests.
Allopurinol Nursing Interventions
- Monitor the patient for signs of liver and kidney impairment.
- Monitor for skin rashes or allergies.
- Instruct patients not to take other medications without consulting their healthcare provider.
- Provide education regarding healthy lifestyle habits (e.g., diet, exercise) that can help reduce the risk of gout attacks and dysfunction caused by hyperuricemia.
- Encourage the patient to follow up with their healthcare provider regularly for monitoring and adjust dosage length accordingly.
- Encourage patients to report any signs or symptoms of adverse reactions to their healthcare provider immediately.
- Monitor urine output and electrolyte levels closely when using allopurinol with other medications or during prolonged treatment such as high-dose, long-term, or parenteral therapy.
- Assess the patient’s compliance with medication and lifestyle changes.
- Provide patient education regarding side effects, drug interactions, and important information about allopurinol therapy.
- Monitor for signs of anemia (pallor, fatigue) due to the risk associated with thrombocytopenia or leukopenia.
- Encourage the patient to follow up with their healthcare provider regularly for monitoring and adjust dosage length accordingly.
- Monitor blood levels of uric acid periodically to ensure that target concentrations are being achieved.
- Inform the patient of possible interactions between allopurinol and alcohol, other medications, or foods (e.g., shellfish).
Teaching points
- Advise the patient to take the drug following meals.
- Warn against taking over-the-counter medications without consulting a healthcare provider, as many of these preparations contain vitamin C or other agents that may increase the risk of kidney stones.
- Inform them of potential side effects, such as exacerbation of gouty attack or renal stones (which can be reduced by drinking 2.5-3 liters/day), nausea, vomiting, loss of appetite (take after meals or eat smaller meals), drowsiness and unusual bleeding or bruising.
- Instruct to contact a healthcare provider if fever, chills, a gout attack, numbness or tingling, flank pain, or skin rash occurs.
References
- https://en.wikipedia.org/wiki/Allopurinol
- https://www.drugs.com/allopurinol.html
Mrs. Marie Brown has been a registered nurse for over 25 years. She began her nursing career at a Level I Trauma Center in downtown Chicago, Illinois. There she worked in the Emergency Department and on the Surgical Intensive Care Unit. After several years, she moved to the Midwest and continued her nursing career in a critical care setting. For the last 10 years of her nursing career, Mrs. Brown worked as a flight nurse with an air ambulance service. During this time, she cared for patients throughout the United States.