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Drug Class: Commonly Known As: Category:
Antiobesity Agent Xenical

Orlistat - Side Effects, Precautions, and Contraindications

What side effects can Orlistat cause?

Common side effects include:

  • ​Oily stool and/or leaking of oil from the anus
    • This is due to how the medication works.
  • Abdominal distention (enlarged or swollen abdomen), stomach pain and bloating
    • You may consider reducing your fat intake to reduce these side effects.
  • Other side effects include headaches, flu-like symptoms such as cough and runny nose, low blood sugar level (which may include symptoms of shakiness, dizziness, sweating), sudden or increased number of bowel movements, tiredness or irregular menstrual periods in women.

Consult your healthcare professional if the symptoms do not go away or become bothersome.

Rare but serious side effects include:

  • Bleeding from the anus or blood in your stool or vomit
  • Dark urine or light coloured stools, nausea, vomiting, loss of appetite, stomach pain, yellowing of your eyes or skin

The symptoms of a drug allergy include one or more of the following:

  • Swollen face/eyes/lips/tongue
  • Difficulty in breathing
  • Itchy skin rashes over your whole body

If you experience any of these symptoms, you should stop your medication and see your healthcare professional immediately.

Before taking Orlistat , what precautions must I follow?

​Inform your healthcare professional if:

  • You are allergic to this medication or any of the other ingredients of this medication
  • You are pregnant, planning to become pregnant, or breastfeeding
  • You are taking any other medications, including supplements, traditional medications and herbal remedies
  • You have liver or kidney problems
  • You have chronic malabsorption syndrome, a condition where you have problems absorbing nutrients from food.
  • You have cholestasis, a condition where the flow of bile from the liver is blocked
  • You have diabetes   

This medication may reduce the absorption of fat soluble vitamins (A, D, E, K) and can cause low vitamin levels in rare cases, if taken continuously for a long time. You can take vitamin supplements that contain vitamin A, D, E and K to make sure you get enough nutrition.

You should eat a well-balanced diet and split your fat intake evenly over your three main meals. To find out more about planning a well-balanced diet, talk to your healthcare professional or dietitian.

Taking orlistat with a meal that contains a lot of fat may increase your chance of experiencing side effects such as bloating or oily, fatty stools. Avoid taking fatty food between meals.

What food or medicine must I avoid when I take Orlistat ?

​If you are taking any multivitamin supplement, space orlistat at least two hours before or after taking the supplement.

Inform your healthcare professional if you are taking the following medication:

  • Anti-retroviral medications used to treat human immunodeficiency virus (HIV) infection or hepatitis B infection
  • Medications for seizures
  • Medications for diabetes such as Acarbose
  • Other medication such as Cyclosporin and Warfarin

Orlistat - Additional Information

  • Updated on 9/30/2019 12:00:00 AM
  • Article contributed by PSS National Medication Information Workgroup PSS National Medication Information Workgroup
The information provided is not intended as medical advice. Terms of use. Information provided by SingHealth

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