Olsalazine (Oral)

Anti-inflammatory drug olsalazine is usually used to reduce bowel inflammation associated with ulcerative colitis.


Olsalazine is an anti-inflammatory commonly used to treat ulcerative colitis and its various symptoms, such as bowel inflammation, diarrhea, abdominal pain and rectal bleeding. It works by interrupting the production of chemicals in the body which cause these inflammatory responses. It helps to prevent flareups of the condition and is designed for long term use. Sometimes it is also used for other purposes and conditions.

In the US, olsalazine is known by the brand name Dipentum, and it is only available with a doctor's prescription. It is designed to be taken orally and is provided in capsule form.

Conditions Treated?

Type Of Medicine?

  • Anti-inflammatory

Side Effects

Olsalazine can cause unwanted effects as well as its needed effects. While many of these are mild and can be tolerated against the benefits of the drug, some side effects are serious and need urgent medical attention.

If you experience any of the following side effects while taking olsalazine, consult your doctor immediately:

  • Severe back or stomach pain
  • Swelling of the stomach
  • Nausea or vomiting
  • Bloody diarrhea
  • Yellow eyes or skin
  • Skin rash
  • Fever

The following side effects are minor and only require medical attention if they become severe or persistent. Some people find that they dissipate once their body adjusts to the medicine. If you have questions about them or become concerned that a minor side effect is affecting you too severely, consult your doctor.

  • Abdominal or stomach pain
  • Stomach upset
  • Diarrhea
  • Loss of appetite
  • Aching muscles and joints
  • Headache
  • Dizziness or drowsiness
  • Difficulty sleeping
  • Acne

It is possible that patients could experience other side effects not listed here. If so, the effects should be reported to a doctor immediately. They could also be reported to the FDA, or a doctor may do this on the patient's behalf.


The amount of olsalazine a patient takes will depend on the severity of their condition and other factors, such as their age or medical history. Always follow your doctor's instructions and do not take more olsalazine than prescribed, or take it more often than prescribed, as this could increase the risk of side effects. If you take too little olsalazine, the medicine may not be effective. Do not stop taking the drug or change your dose without your doctor's instruction, even if you feel well.

The average dose of olsalazine for adults is 500 mg, two times each day. For children, the use and dose of olsalazine must be determined by a doctor.

How to take olsalazine

Olsalazine should be taken with food to minimize stomach upset or discomfort. If you experience severe discomfort after taking each dose of olsalazine, consult your doctor. You should swallow each capsule whole with a full glass of water. Do not break, chew or crush the capsules.

If you miss a dose of olsalazine, take it as soon as you remember unless it is almost time for your next dose. In this case, simply skipped the missed dose and continue with your usual dosing schedule. Never double doses of olsalazine as doing so could cause severe stomach upset and increase the risk of other side effects.

It is very important that you do not miss doses of olsalazine, because it may make you more susceptible to flareups of ulcerative colitis. Try to take your doses at around the same times each day to minimize the risk of forgetting. For example, you could take one dose at breakfast time and the second with your evening meal, and do the same every day until it becomes a habit.

If your symptoms of ulcerative colitis do not improve after taking olsalazine, or they become worse, consult your doctor.


Olsalazine can interact with a wide range of other drugs, so it's very important that you tell your doctor about all the medicines you take. This includes those prescribed by a doctor, those purchased over the counter, and any herbal supplements or vitamins that you take. Some interactions may increase the risk of side effects, while others may cause other medical complications or make some medicines less effective.

Sometimes interactions occur which are not recommended, but may be tolerated if the benefits of both drugs outweigh potential risks of interaction. If your doctor continues to prescribe both medicines, they may adjust dosages or give you new instructions as to the times of day that you take the medicines in order to reduce the risk of complications.

It is particularly important that your doctor knows if you are taking anticoagulant medicines. Anticoagulants are often referred to as 'œblood-thinners'. Warfarin (also known as Coumadin and Jantoven) is a particularly common example of an anticoagulant.



Tell your doctor about all the allergies you suffer from, including food, drug, chemical and pollen allergies. They will check that you are not allergic to any ingredients in olsalazine.

If you have had an allergic reaction to olsalazine, aspirin, or aspirin-like medicines (salicylates) in the past, you may not be able to take olsalazine. If you have asthma, you may also be unable to take olsalazine because the condition may worsen breathing problems should they occur during allergic reaction.

If you notice any symptoms of allergic reaction when taking olsalazine, call your doctor or visit the emergency room immediately. Signs of allergy include:

  • Swelling of the eyelids, face, lips, tongue, or throat
  • Rash, hives, or itching
  • Wheezing
  • Tightness of the chest
  • Labored breathing

Interactions With Medical Conditions

Make sure your doctor knows about all the medical conditions you currently have, as well as those you have suffered from in the past. You may not be able to take olsalazine with certain conditions, while others may result in you being prescribed a lower dose.

It is particularly important to tell your doctor if you have kidney disease or liver disease, as olsalazine could cause further damage to these organs. Your doctor may administer lower doses of olsalazine to minimize liver or kidney damage or other complications. They may want to monitor you more closely and administer frequent tests to assess your liver or kidney function.

Tell your doctor straight away if you notice signs of kidney problems, such as difficulty or inability to pass urine, sudden changes to the volume or urine passed, blood in the urine, or sudden weight gain.

Sunlight sensitivity

Olsalazine can increase the skin's sensitivity to sunlight. To avoid severe sunburn, wear protective clothing, sunscreen and sunglasses whenever you plan to be exposed to the sun.

Pregnancy and breastfeeding

Olsalazine is an FDA pregnancy category C drug. Animal studies have demonstrated risks to the fetus, and there have not been enough controlled human studies to assess the effects of olsalazine on human fetuses. For this reason, olsalazine should be avoided during pregnancy unless the benefits of the drug far outweigh potential risks to the fetus. If you become pregnant while taking olsalazine, consult your doctor immediately.

There is evidence of olsalazine causing diarrhea in nursing infants when it is taken by a mother while she is breastfeeding. For this reason, the drug is not recommended for breastfeeding women. Depending on the value of the drug to the patient, mothers are usually advised to either avoid olsalazine or avoid breastfeeding in order that they can safely take olsalazine.

Pediatric use

Studies into olsalazine have so far only been performed on adults. The safety and usefulness of the drug for children in unknown. For this reason, doctors determine the use and dose of the drug in children on a case by case basis.

Geriatric use

There is no evidence to suggest that olsalazine is any less effective when administered to elderly patients than it is when taken by younger adults. However, elderly patients are more likely to have age-related kidney or liver problems. For this reason, doctors may be more cautious about prescribing olsalazine to geriatric patients. They may initially prescribe lower doses of the drug and gradually increase the dose following close monitoring and tests.


Olsalazine should be stored at room temperature in the container it was provided to you in. Keep the lid tightly closed when not in use, and keep the container out of reach and sight of children. Avoid allowing the medicine to freeze, and do not expose it to direct light, heat or moisture.

If you have expired or unused olsalazine, ask your healthcare provider how to safely dispose of it. They, or your pharmacy or local garbage or recycling department, may provide a medicine take-back scheme. Do not simply throw the medicine in the trash or flush it down the toilet as it could cause harm to other people or to the environment.


Olsalazine is an anti-inflammatory medicine commonly prescribed to patients with ulcerative colitis to prevent flareups. It can help to control symptoms such as diarrhea, abdominal pain, rectal bleeding, and bowel inflammation. It is designed to be taken daily for a long period of time.

Olsalazine is administered in capsule form which should be taken by mouth. Most patients take two doses each day. Each dose should be swallowed with a full glass of water and taken at the same time as food. It is important to take every dose of olsalazine, as missing doses could lead to a flareup. Patients should not stop taking the drug unless instructed do so by a doctor, even if they feel well.

Patients with asthma, kidney disease, or liver disease may not be able to take olsalazine. It may also be unsuitable for those who have had an allergic reaction to olsalazine, or to aspirin or aspirin-like medicines. It is not recommended for use during pregnancy or while breastfeeding unless potential benefits of the drug far outweigh potential risks to the fetus or nursing infant. The safety and efficacy of the drug for children has not been established.

Olsalazine can cause mild stomach upset and abdominal pain, headache, sleeping problems, and acne. These do not need medical attention unless they become severe. Patients who notice bloody diarrhea, severe stomach or back pain, nausea or vomiting, yellow skin or eyes, or problems urinating should consult their doctor immediately.