allopurinol vs pegloticase

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Side-by-side comparison of allopurinol and pegloticase. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.

major Known Drug Interaction

( 7.2 ) Pegloticase: Discontinue and refrain from initiating treatment with allopurinol tablets. Pegloticase Clinical Impact Concomitant use of allopurinol tablets and pegloticase may potentially blunt the rise of serum uric acid levels and increase the risk of pegloticase related anaphylaxis in patients whose uric acid level increase to above 6 mg/dL. Intervention Discontinue and do not institute allopurinol tablets therapy during treatment with pegloticase.

Drug Class
allopurinol Xanthine Oxidase Inhibitor
pegloticase Recombinant Uricase
Type
allopurinol Prescription
pegloticase Prescription
Summary
allopurinol

Allopurinol is a medicine that lowers uric acid levels in your body. It helps prevent gout attacks and other problems caused by high uric acid.

pegloticase

Krystexxa is a medicine used to treat chronic gout in adults when other treatments don't work well enough. It helps lower uric acid levels in your blood.

What It Treats
allopurinol

This medicine is used to manage gout in adults. Gout causes painful attacks, joint damage, and kidney problems. Allopurinol is also used in adults and children with leukemia, lymphoma, and solid tumors who are getting cancer treatment. It helps manage high uric acid caused by the cancer treatment. It can also help adults who get calcium oxalate kidney stones often.

pegloticase

Krystexxa is used to treat chronic gout in adults. This is for people whose gout is not well controlled with other medicines. It helps lower uric acid levels in your blood to reduce gout symptoms.

How It Works
allopurinol

Allopurinol works by blocking an enzyme called xanthine oxidase. This enzyme helps your body make uric acid. By blocking it, allopurinol reduces the amount of uric acid in your blood and urine.

pegloticase

Krystexxa contains an enzyme that breaks down uric acid in your body. This helps to lower the amount of uric acid in your blood. Lowering uric acid can reduce gout symptoms.

Common Side Effects
allopurinol
  • Diarrhea
  • Nausea
  • Increased liver enzyme levels
  • Gout attacks
  • Skin rash
pegloticase
  • Gout flares
  • Nausea
  • Infusion reactions
  • Joint pain
  • COVID-19
FAERS Reports
allopurinol
  • Diarrhoea 8,423
  • Fatigue 7,965
  • Dyspnoea 7,658
  • Nausea 7,063
  • Death 6,665
pegloticase
  • Gout 539
  • Blood Uric Acid Increased 378
  • Infusion Related Reaction 358
  • Therapeutic Response Decreased 240
  • Dyspnoea 166
Serious Warnings
allopurinol

Allopurinol can cause serious skin reactions that can be deadly. Stop taking this medicine and get medical help right away if you get a skin rash or any other signs of an allergic reaction.

pegloticase

Krystexxa can cause serious allergic reactions, including anaphylaxis, during or after the infusion. You should receive Krystexxa in a healthcare setting where anaphylaxis can be treated. If you have G6PD deficiency, you should not take Krystexxa, as it can cause red blood cell problems.

Pregnancy
allopurinol

Allopurinol may harm your unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant. It is not recommended to breastfeed while taking this medicine because it can pass into breast milk.

pegloticase

It is not known if Krystexxa can harm your unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant. It is not known if Krystexxa passes into breast milk, so it should not be used when breastfeeding unless the benefit outweighs the risk.

Also Compare, Nearby Drugs

Compare allopurinol with

How to Read This allopurinol vs pegloticase Comparison

allopurinol is classified in the Xanthine Oxidase Inhibitor drug class, while pegloticase sits within the Recombinant Uricase class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.

Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, allopurinol has 37,774 submissions while pegloticase has 1,681. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known major interaction flagged in FDA labeling, attributed to allopurinol can hide changes in your blood levels that warn doctors of a possible severe allergic reaction to pegloticase.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for allopurinol or pegloticase.

Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.