Allopurinol
About Allopurinol
Allopurinol is a prescription medication used to prevent gout attacks and manage certain types of kidney stones. It is also prescribed to lower high uric acid levels in patients undergoing chemotherapy treatments for cancer.
To achieve the best results, you must take Allopurinol consistently every day as directed, even when you do not have active symptoms. It is best taken after a meal to help prevent stomach irritation, and pairing it with dietary adjustments like limiting purine-rich foods can greatly support your treatment.
While Allopurinol is highly effective, some people may experience mild side effects such as drowsiness or temporary stomach upset. However, you should contact your doctor immediately if you develop a skin rash, peeling skin, dark urine, or yellowing of the skin or eyes.
Before starting this medication, talk to your doctor if you have kidney or liver issues, thyroid problems, or heart conditions. Do not take this medicine if you have had a severe allergic reaction to it in the past.
This medication can interact with other treatments, such as blood thinners or certain antibiotics, which can increase your risk of severe side effects. It is important to consult your doctor or pharmacist if you are pregnant, planning to become pregnant, breastfeeding, or are an older adult.
Uses of Allopurinol
Medicinal Benefits
Allopurinol helps lower uric acid levels in the body, preventing the formation of uric acid crystals that cause gout and certain types of kidney stones. Regular use helps provide long-term control and reduces the risk of recurrent attacks.
- Prevents Gout Attacks: Lowers uric acid levels, helping prevent painful gout flare-ups and reducing joint inflammation over time.
- Protects Joint Health: Helps prevent the formation of uric acid crystals, reducing the risk of long-term joint damage caused by recurrent gout.
- Reduces the Risk of Kidney Stones: Helps prevent uric acid kidney stones by lowering the amount of uric acid in the urine.
- Supports Kidney Function During Cancer Treatment: Helps reduce uric acid levels in patients receiving chemotherapy or radiation therapy, lowering the risk of tumour lysis syndrome and protecting kidney function.
- Improves Long-Term Quality of Life: By preventing gout attacks and reducing uric acid-related complications, it helps maintain mobility, comfort, and overall well-being.
Directions for Use
- Take Allopurinol with food to avoid stomach upset or as advised by a doctor.
- Recommended to take the medicine once or twice a day or as advised by your doctor.
- Swallow the medicine as a whole with a glass of water.
- Do not crush, break, or chew it.
Storage
Side Effects of Allopurinol
Common Side Effects (Usually mild)
- Nausea or mild upset stomach
- Drowsiness or feeling tired
- Diarrhoea
- Temporary increase in gout flares (when first starting)
Serious Side Effects (Consult your doctor right away)
- Skin rash, hives, or peeling skin (which can be a sign of a rare but severe allergic reaction)
- Yellowing of your eyes or skin, dark urine, or severe stomach pain (signs of liver damage)
- Fever, chills, sore throat, or unusual bruising and bleeding
- Painful, difficult, or bloody urination
Medicines Containing this Salt
View AllDrug Warnings
- Watch for early signs of skin rash: A rash of any kind can be a sign of a severe allergic reaction. Stop taking Allopurinol immediately and seek emergency medical care if you notice a skin rash, peeling, or sores on your lips or eyes.
- Do not stop during a flare-up: It is common to experience more gout attacks during the first few months of starting Allopurinol. Keep taking the medication consistently and talk to your doctor, who may prescribe other temporary pain relievers to manage these flares.
- Be cautious with activities: Since this medicine can cause drowsiness, avoid driving or operating heavy machinery until you know how it affects you.
- Monitor your lab work: Your doctor will likely order regular blood tests to check your uric acid levels and monitor your kidney and liver function while you are on this medicine.
- Inform all healthcare providers: Always tell any doctor, dentist, or pharmacist that you are taking Allopurinol before starting any new treatments or undergoing medical procedures.
Drug Interactions
- Azathioprine or mercaptopurine: Allopurinol can significantly increase the levels of these immune-suppressing medicines in your body, which can lead to severe, life-threatening side effects. Your doctor will need to adjust the doses.
- Amoxicillin or ampicillin: Taking these antibiotics with Allopurinol may increase your risk of developing a skin rash.
- Warfarin or other blood thinners: This medicine can increase the effects of blood thinners, potentially raising your risk of bleeding.
- Thiazide diuretics (water pills): These medications can increase the concentration of Allopurinol in your blood, raising the risk of severe allergic reactions, especially in people with kidney problems.
- Cyclosporine: Allopurinol may increase cyclosporine levels in the body, raising the risk of side effects. Your doctor may monitor you more closely or adjust your treatment.
- ACE inhibitors (such as captopril): Taking these medicines with Allopurinol may increase the risk of allergic reactions or blood-related side effects, particularly in people with kidney disease.
Drug-Drug Interactions Checker List:
Safety Advice
Alcohol
unsafeAllopurinol should not be taken along with alcohol, as it increases uric acid levels.
Pregnancy
cautionAllopurinol is a Category C pregnancy drug. If you are pregnant, think you may be pregnant or are planning to have a baby, ask your doctor for advice before taking this medicine.
Breast Feeding
unsafeAllopurinol is excreted in human breast milk, so it is not recommended during breastfeeding.
Driving
unsafeAllopurinol may cause some individuals to feel drowsy. Do not drive or operate dangerous machinery if you are affected.
Liver
cautionAllopurinol to be taken with caution, especially if you have a history of Liver diseases/conditions. The dose may have to be adjusted by your doctor.
Kidney
cautionAllopurinol to be taken with caution, especially if you have a history of Kidney diseases/conditions. The dose may have to be adjusted by your doctor.
Children
unsafeAllopurinol hasn’t been studied and shouldn’t be used in people younger than 18 years to treat gout or kidney stones.
Habit Forming
Diet & Lifestyle Advise
- Stay well-hydrated: Drink 8 to 10 glasses of water daily to help your kidneys flush out uric acid and reduce the risk of kidney stones.
- Limit high-purine foods: Minimise your intake of foods that trigger uric acid production, such as red meat, organ meats (like liver), seafood (especially shellfish and anchovies), and yeast extracts.
- Avoid high-fructose corn syrup: Limit sugary drinks, sodas, and processed sweets, as fructose can increase uric acid levels in the body.
- Limit alcohol intake: Avoid or severely restrict beer and hard liquor, as they can interfere with how your body eliminates uric acid and can trigger sudden gout attacks.
- Maintain a healthy weight: Gradual weight loss can lower uric acid levels, but avoid extreme fasting or rapid crash diets, which can temporarily spike uric acid and trigger gout attacks.
Special Advise
- Drink at least 8 glasses of water or other fluids each day while taking Allopurinol, unless your doctor advises otherwise. If you have kidney disease, consult your physician before increasing fluid intake.
- If you are intolerant to sugars, please consult your doctor before starting Allopurinol.
- Your doctor will monitor your kidney function constantly before and during treatment with Allopurinol.
- A liver function test should be performed regularly to monitor liver enzymes, as Allopurinol may cause fluctuations in these enzymes.
Patients Concern
Disease/Condition Glossary
Gout: It is a type of inflammatory (allergic reaction) to uric acid crystals that form and accumulate inside the feet, knuckles, and surrounding joints due to high uric acid levels in the blood. Common symptoms include severe joint pain, swelling, redness, tenderness, and stiffness.
Kidney and bladder stones: It is a problem in which hard deposits of minerals and salts form in the kidneys or bladder, leading to stones. Kidney stones can cause severe pain, blood in urine, and urinary obstruction, while bladder stones may lead to difficulty passing urine, pain, and frequent urination. Both types are often linked to high uric acid levels, dehydration, or certain medical conditions.
FAQs
Allopurinol is used to treat gout (increased uric acid leading to inflammation), kidney stones, and bladder stones. It decreases blood uric acid levels in the body.
Allopurinol contains allopurinol, which works by blocking the action of xanthine oxidase, the enzyme responsible for the production of uric acid. It stops uric acid formation inside the body and prevents crystal buildup, making it effective in managing gout and kidney/bladder stones.
If you are taking Allopurinol and it makes you vomit, then your contraceptive pill would not be effective, and it could lead to an unwanted pregnancy. If you are of childbearing age, inform your doctor before starting Allopurinol and use another form of contraceptive like condoms.
Generally, when Allopurinol is administered to elderly patients (aged> 65 years), the dose is reduced based on the patient’s condition. Also, if you mention all underlining disease you suffer from, which could affect Allopurinol, the dose will be adjusted accordingly by your doctor.
Yes, Allopurinol can cause drowsiness in some people. It can even make you feel dizzy or have a problem with coordination. It is advisable to avoid driving or operating machinery to avoid any unpleasant side effects.
No, Allopurinol is not an anti-inflammatory medicine. It works by inhibiting the enzyme xanthine oxidase, which catalyses the formation of uric acid. It inhibits uric acid formation within the body without affecting essential cellular and systemic mechanisms.
It may take several weeks to lower uric acid levels before you begin to feel better or notice a significant reduction in gout attacks.
Allopurinol may cause side effects such as nausea, vomiting, diarrhoea, stomach upset, or drowsiness. If these side effects persist or worsen, please consult your doctor.
If you forget to take a dose of Allopurinol, take it as soon as you remember. But, if it is time for your next dose, skip the missed dose and take your regular dose. Do not take a double dose to make up for a forgotten dose.
Store Allopurinol in a cool, dry and dark place. Protect from direct sunlight and moisture. Keep it out of sight and reach of children.
No, you should not stop taking this medicine when your pain resolves. Allopurinol is a preventive treatment that must be taken daily to keep your uric acid levels stable and prevent future attacks. Stopping it suddenly can cause your uric acid levels to spike, triggering a new gout attack. Talk to your doctor before making any changes to your medication routine.
When you first start taking this medicine, the sudden lowering of uric acid levels can cause existing crystals in your joints to shift and dissolve, which can temporarily trigger or worsen gout pain. This is a common response and does not mean the medication is not working. Your doctor may prescribe an anti-inflammatory medicine to help manage this initial phase. Talk to your doctor if the pain is severe or prolonged.
It is highly recommended to avoid or limit alcohol, especially beer, while taking this medicine. Alcohol increases uric acid production and prevents your kidneys from filtering it out, which can trigger gout attacks and reduce the effectiveness of Allopurinol. Talk to your doctor about what level of alcohol consumption, if any, is safe for you.
If you notice any skin rash, itching, peeling, or hives, stop taking the medication immediately and contact a doctor or seek emergency medical care. A rash can be an early sign of a rare but life-threatening allergic reaction. Do not take another dose until a healthcare professional has evaluated your skin. Talk to your doctor.
You should take Allopurinol after a meal to help minimise potential stomach upset, indigestion, or nausea. Drinking a full glass of water with each dose is also recommended. If stomach issues persist even when taking the medicine with food, talk to your doctor.
Allopurinol is actually used to protect the kidneys from damage caused by high uric acid and kidney stones. However, because the drug is cleared by the kidneys, individuals with pre-existing kidney disease require carefully adjusted doses to prevent the drug from building up in the body. Your doctor will monitor your kidney function with routine blood tests. Talk to your doctor if you have concerns about your kidney health.
The safety of Allopurinol during pregnancy and breastfeeding is not fully established. It should only be used if the potential benefit justifies the risk to the baby. If you are pregnant, planning to become pregnant, or are currently breastfeeding, talk to your doctor to discuss safer alternative treatments.
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