Probenecid

Sounds like 'pro-ben-i-sid'

Easy-to-read medicine information about probenecid – what it is, how to take probenecid safely and possible side effects.

Type of medicine Also called
  • Medicine to prevent gout
  • Belongs to a group of medicines known as urate lowering therapy
  • Probenecid-AFT

What is probenecid?

Probenecid is used to prevent gout attacks or flares. It is used when allopurinol cannot be taken or hasn’t worked well. Sometimes probenecid is used with allopurinol. Probenecid is not a treatment for a gout flare — it does not relieve short-term pain and swelling, but you must keep taking probenecid if you get an attack and are already taking it (see special instructions below). Probenecid is available as tablets.  Read more about gout.

How does probenecid work?

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.

Dose

  • 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:

Date  Morning Evening
     
     
     
Notes: 

  

How to take probenecid

  • 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.

Special instructions

  • 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.

Precautions – before taking probenecid

  • Do you have problems with your kidneys or have you had kidney stones?
  • Do you have any blood disorders?
  • Are you pregnant or breastfeeding?
  • Are you taking any other medicines? This includes any medicines you buy without a prescription, such as herbal and complementary medicines.

If so, it’s important that you tell your doctor or pharmacist before you start probenecid, or any new medicines. Sometimes a medicine isn’t suitable for a person with certain conditions, or it can only be used with extra care.

Possible side effects

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.

Side effects What should I do?
  • Feeling sick (nausea)
  • Upset stomach
  • Indigestion
  • Vomiting
  • Take probenecid with food
  • Tell your doctor if troublesome
  • Headache or dizziness
  • Loss of appetite
  • Flushing
  • These are quite common when you first start taking probencid, and usually go away with time.
  • Tell your doctor if troublesome
  • Signs an allergic reaction such as skin rashes, itching, blisters, peeling skin, swelling of the face, lips, mouth or have problems breathing


  • Tell your doctor immediately or ring HealthLine. 
  • Signs of problems with your kidneys such as passing urine more often than usual, pain when passing urine, blood in your urine, severe back pain.
 
  • Tell your doctor immediately or ring HealthLine. 

Interactions

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.

Learn more

The following links have more information on probenecid.

Probenecid (Māori) New Zealand Formulary Patient Information 

References

  1. Managing gout in primary care BPAC, 2018
  2. Probenecid New Zealand Formulary
Credits: Sandra Ponen, pharmacist. Reviewed By: Angela Lambie, Pharmacist, Auckland Last reviewed: 30 Apr 2018