Allopurinol

Price range: £10.95 through £25.95

Allopurinol tablets are a prescription treatment that lowers uric acid levels to manage chronic gout and kidney stones.
Used long-term to prevent flare-ups.
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Description

Allopurinol is a well-established medication used to manage conditions caused by high uric acid levels, such as gout and uric acid kidney stones. It is also used to control uric acid spikes during cancer treatments involving chemotherapy.

This prescription-only tablet works by reducing the production of uric acid in the body. Uric acid forms when purines (found in many foods and drinks) are broken down. Excess uric acid in the bloodstream can crystallise in joints or kidneys, causing painful inflammation or stone formation.

Allopurinol is taken daily and is most commonly available in 100mg or 300mg strengths, adjusted according to your blood uric acid levels and kidney function. It helps to prevent gout attacks, not treat them during flare-ups. As a result, it is often paired with anti-inflammatories like colchicine or NSAIDs during the first few months of therapy to reduce the risk of flare-ups triggered by uric acid shifts.

Regular blood tests are needed to monitor your kidney function and uric acid levels. Most patients will notice a reduction in flare-ups within 2–3 months of starting treatment. It is critical to continue taking Allopurinol as prescribed even if symptoms improve or disappear.

How It Works

Allopurinol inhibits an enzyme called xanthine oxidase, which is responsible for converting purines into uric acid. By reducing uric acid production at its source, the medication helps prevent crystal build-up in the joints and urinary tract.

Why Choose Allopurinol

Proven and long-term treatment for gout and hyperuricaemia

Reduces risk of gout flares and kidney stone formation

Often part of a preventive management plan after repeated flares

Can be used with other medications to enhance symptom control

Low cost, high efficacy for chronic uric acid conditions

Important Note

Do not stop treatment abruptly without speaking to your doctor. Stay hydrated to reduce the risk of kidney stones. Avoid high-purine foods and alcohol during treatment.

Dosage may need adjustment in patients with kidney or liver impairment. Inform your GP if you experience rashes or unusual symptoms, as rare hypersensitivity reactions may occur.

Directions

Note: Always follow your doctor’s instructions.

  • Take Allopurinol once daily, preferably after a meal

  • Dosage varies, commonly 100mg to 300mg daily

  • Swallow with water

  • Maintain hydration (1.5–2L fluids per day)

Storage:

  • Store below 25°C

  • Keep in original packaging

  • Keep away from children

Ingredients

  • Active Ingredient:

    • Allopurinol (typically 100mg or 300mg)

  • Other ingredients may include:

    • Lactose monohydrate

    • Maize starch

    • Magnesium stearate

Side Effects

Common:

  • Rash

  • Nausea

  • Diarrhoea

  • Headache

Serious (rare):

  • Hypersensitivity syndrome

  • Liver problems

  • Severe skin rashes

Stop treatment and seek medical help if you notice a rash, fever, or swollen glands.

Warnings

  • Not for use during active gout attacks (start post-flare)

  • Caution in kidney or liver disease

  • May interact with anticoagulants, chemotherapy agents, and antibiotics

  • Not recommended during pregnancy unless advised by a GP

  • Yes. Allopurinol can interact with azathioprine, mercaptopurine, anticoagulants, and certain antibiotics. Always disclose your full medication list to your doctor.
  • No. It is usually not started during an active flare, but if you're already on it, do not stop taking it during the flare unless advised by your GP.
  • Allopurinol starts working within 2 to 3 days, but optimal uric acid reduction typically takes 2 to 6 weeks of regular use.
  • Yes. Allopurinol is intended for long-term management of chronic gout and hyperuricaemia under medical supervision
  • Allopurinol is prescribed to lower uric acid levels in conditions such as gout, kidney stones, and certain types of chemotherapy-related uric acid elevations.