Probenecid

Probenecid helps reduce urate levels in your blood (serum urate) and reduce gout attacks.

• Uric acid is a normal product of your metabolism and in the blood, uric acid becomes urate.
• When urate levels are high, crystals can form around joints causing inflammation, pain and damage. This is known as gout.
• To reduce gout attacks, it is important to keep your serum urate level below 0.36 mmol/L.
• When the serum urate is below 0.36mmol/L no new crystals form and crystals that are in your joints or skin can dissolve.

Read more about gout.

• The dose of probenecid will be different for different people.
• Your doctor will usually start you on a low dose of 250 milligrams twice a day for 1 week, and increase it slowly over a few weeks. 
• Your doctor will test your serum urate with a blood test and increase your probenecid dose until a serum urate level of less than 0.36 mmol/L is reached.
• The maximum dose is 1 gram twice daily.
• Always take your probenecid exactly as your doctor has told you. The pharmacy label on your medicine will tell you how much to take, how often to take it, and any special instructions.
• Probenecid takes 2 to 3 months to become fully effective.

My dose is:

• Take probenecid with food to prevent stomach upset.
• Take probenecid twice a day with a full glass of water. It is important to drink plenty of water while you are taking probenecid because kidney stones can develop if you do not drink enough fluid.  
• Keep taking probenecid every day, even during a gout attack. Probenecid takes 2 to 3 months to become fully effective.
• Limit or avoid drinking alcohol; it can increase your risk of gout attacks.
• If you forget to take your tablet, take it as soon as you remember. But, if it is nearly time for your next tablet, just take the next tablet at the right time. Do not take double the dose.
• Do not stop taking probenecid suddenly; speak to your doctor or nurse before stopping. Stopping probenecid quickly can make your gout worse.

Here are some things to know when you're taking probenecid. Other things may be important as well, so ask your healthcare provider what you should know about.

• Other medicines: Probenecid may interact with a few medications and herbal supplements, so check with your doctor or pharmacist before starting allopurinol or before starting any new medicines.
• Keep yourself hydrated: probenecid can increase your chance of getting kidney stones. Drink at least 6 to 8 full glasses of water a day while taking probenecid to prevent kidney stones, unless directed to do otherwise by your doctor.
• Increased gout attacks: when you start taking probenecid, gout attacks can still happen in the first few weeks or months. When you start probenecid, your doctor will also prescribe a low-dose non-steroidal anti-inflammatory (NSAID) or colchicine for 6 months to reduce the chances of these attacks. Keep taking probenecid every day, even during a gout attack.
• Blood tests: when you first start taking probenecid, you will need to have blood tests to monitor your serum urate levels every 4 weeks until the target level has been reached. Then you will need blood tests 3-6 monthly to check serum urate and your kidney function.

Like all medicines, probenecid can cause side effects, although not everyone gets them. Often side effects improve as your body gets used to the new medicine.