Allopurinol is a medication commonly used to treat conditions caused by high levels of uric acid in the body. It belongs to a class of drugs known as xanthine oxidase inhibitors.

Drug Name: Zyloprim

Active Ingredient: Allopurinol

Allopurinol tablets



Form: Tablet

Type: Generic

Prescription Required: Rx

Availability: In Stock

The primary purpose of allopurinol is to lower and maintain the levels of uric acid in the blood. It achieves this by inhibiting the production of uric acid in the body, thereby preventing the formation of uric acid crystals that can lead to conditions such as gout and kidney stones.

Gout: Allopurinol is frequently prescribed to individuals with gout, a type of arthritis caused by the buildup of uric acid crystals in the joints. By reducing the levels of uric acid, allopurinol helps to prevent gout attacks and minimize the associated pain and inflammation.

Kidney stones: High levels of uric acid can also contribute to the formation of kidney stones. Allopurinol may be used as a preventive measure to lower uric acid levels and decrease the likelihood of kidney stone formation.

Allopurinol is typically taken orally in the form of tablets or capsules. The dosage and duration of treatment will depend on various factors, including the severity of the condition, uric acid levels, and individual response to the medication.

How to use

Here are some general guidelines on how to use Allopurinol:

  1. Timing: Allopurinol is usually taken once daily, preferably after a meal or with food. Taking it with food can help minimize gastrointestinal upset.
  2. Hydration: Drink plenty of fluids, such as water, throughout the day to maintain adequate hydration. This can help prevent kidney stones and promote the elimination of uric acid from the body.
  3. Compliance: It may take several weeks or months of consistent use for Allopurinol to effectively reduce uric acid levels and prevent gout attacks or kidney stone formation. It is important to continue taking this drug as prescribed, even if you are not experiencing immediate symptoms.
  4. Follow-up: Regularly visit your doctor for follow-up appointments to monitor your uric acid levels and assess the effectiveness of the medication. Your doctor may adjust the dosage if necessary.


The dosage of Allopurinol will depend on various factors, including the severity of your condition, your uric acid levels, and your doctor's recommendation. It is important to follow your doctor's instructions regarding dosage. The following information provides a general overview, but individual dosages may vary:

For the treatment of gout:

  • The usual starting dose for adults is 100 to 200 milligrams per day, divided into two to three smaller doses. Your doctor may adjust the dose based on your uric acid levels and response to treatment.
  • Maintenance doses typically range from 200 to 600 milligrams per day, depending on the severity of your condition.

For the prevention of uric acid kidney stones:

  • The usual dosage for adults is 200 to 300 milligrams per day, divided into two to three smaller doses.

For patients with impaired kidney function:

  • If you have impaired kidney function, your doctor may adjust the dosage of Allopurinol to ensure it is appropriate for your specific situation.

It is important to note that these dosages are general recommendations, and your doctor will determine the specific dosage that is suitable for you.

Side effects

Like any medication, Allopurinol may cause side effects in some individuals, although not everyone experiences them. Common side effects associated with Allopurinol can include:

  1. Skin reactions: This may include rash, itching, hives, or swelling. In rare cases, severe allergic reactions such as Stevens-Johnson syndrome or toxic epidermal necrolysis may occur.
  2. Gastrointestinal symptoms: This may include nausea, vomiting, diarrhea, or abdominal pain.
  3. Headache
  4. Drowsiness or dizziness
  5. Elevated liver enzymes: In rare cases, Allopurinol may cause changes in liver function tests. Your doctor may monitor your liver function periodically.
  6. Flare-up of gout symptoms: In the initial stages of treatment, Allopurinol may cause an increase in gout symptoms. This usually subsides over time with continued use.

It's important to note that this is not an exhaustive list of side effects. Some individuals may experience different or more severe side effects.

If you experience any severe or persistent side effects, seek medical attention immediately.


To store Allopurinol properly and maintain its quality, follow these guidelines:

  1. Temperature: Keep medicine at room temperature, typically between 20°C and 25°C (68°F and 77°F).
  2. Protect from moisture: Store tablets in a tightly closed container to protect it from moisture. Avoid storing it in areas with high humidity, such as the bathroom.
  3. Protect from light: Keep Allopurinol away from direct sunlight or sources of intense light, as light exposure can degrade the medication.
  4. Keep out of reach of children: Store Allopurinol in a safe place where children cannot access it. It is important to prevent accidental ingestion or misuse.
  5. Original packaging: Store pills in its original packaging or container, with the label intact. This helps in identifying the medication and its expiration date.
  6. Check expiration date: Before using Allopurinol, check the expiration date on the packaging. Do not use the medication if it has expired. Properly dispose of any expired or unused medication following local guidelines and regulations.


In case of an overdose of Allopurinol, it is important to seek immediate medical attention or contact your local poison control center. An overdose of Allopurinol can have serious consequences and requires prompt medical evaluation.

Signs and symptoms of an Allopurinol overdose may include:

  1. Severe skin reactions, such as rash, itching, blistering, or peeling
  2. Unusual bleeding or bruising
  3. Yellowing of the skin or eyes (jaundice)
  4. Severe dizziness or drowsiness
  5. Rapid or irregular heartbeat
  6. Nausea, vomiting, or diarrhea

If you or someone else has taken more Allopurinol than prescribed or suspects an overdose, do not delay seeking medical help. Contact a poison control center or go to the nearest emergency room immediately for evaluation and treatment.

Missed Doses

If you miss a dose of Allopurinol, take it as soon as you remember. However, if it is close to the time for your next scheduled dose, skip the missed dose and continue with your regular dosing schedule. Do not double the dose to make up for a missed one.

It is important to maintain a consistent dosing schedule with Allopurinol to keep uric acid levels under control. Missing a dose occasionally is generally not a cause for concern, but try to take your medication as prescribed to ensure its effectiveness.

If you frequently forget to take your doses or have difficulty remembering, consider setting reminders or using other methods to help you remember, such as alarms, pill organizers, or smartphone apps. Establishing a routine and taking your medication at the same time each day can also be helpful.

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