allopurinol vs theophylline
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Side-by-side comparison of allopurinol and theophylline. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.
minor Known Drug Interaction
Theophylline Clinical Impact Concomitant use of allopurinol doses greater than or equal to 600 mg/day may decrease the clearance of theophylline. Intervention Monitor and adjust theophylline doses as reflected in the prescribing information.
Zyloprim
Theo-24, Elixophyllin
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.
Theophylline is a medicine that helps you breathe easier. It treats the symptoms of asthma and other lung problems.
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.
Theophylline treats the symptoms of long-term asthma and other lung diseases. These include emphysema and chronic bronchitis, which make it hard to breathe. This medicine helps to open up your airways so you can breathe easier.
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.
Theophylline is a bronchodilator. It works by relaxing the muscles in your airways. This allows more air to flow in and out of your lungs.
- • Diarrhea
- • Nausea
- • Increased liver enzyme levels
- • Gout attacks
- • Skin rash
- • Nausea
- • Vomiting
- • Headache
- • Trouble sleeping (insomnia)
- Diarrhoea 8,423
- Fatigue 7,965
- Dyspnoea 7,658
- Nausea 7,063
- Death 6,665
- Dyspnoea 2,273
- Asthma 1,942
- Pneumonia 1,318
- Wheezing 1,306
- Vomiting 1,101
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.
If your theophylline levels get too high in your blood, it can cause serious side effects. These include severe vomiting, irregular heartbeats, and seizures. These can be life-threatening.
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.
It is not known if theophylline can harm an unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant. It is also not known if theophylline passes into breast milk, so talk to your doctor if you are breastfeeding.
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How to Read This allopurinol vs theophylline Comparison
allopurinol is classified in the Xanthine Oxidase Inhibitor drug class, while theophylline sits within the Methylxanthine Bronchodilator 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 theophylline has 7,940. 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 minor interaction flagged in FDA labeling, attributed to taking high doses of allopurinol can make it harder for the body to get rid of theophylline. this can lead to higher levels of theophylline in your system.. 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 theophylline.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.