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Alli: A Weight Loss Drug

(continued)

Who Should Not Take Alli

Always tell your doctor about all the medications you are taking. Alli can interact with certain drugs, affecting their levels in your body or how they work. This may lead to life-threatening consequences.

Do not take Alli if:

Check with your health care provider before taking this drug if you are taking any of the following:

  • Warfarin (a blood thinner)
  • Diabetes medications
  • Thyroid disease medications
  • Other weight loss drugs

In some cases, your dosage of medication may need to be adjusted.

Side Effects of Alli

Loose stools and other bowel movement changes are the most common side effects of Alli. Symptoms typically occur during the first few weeks of treatment and then go away. However, they may continue.

Tell your doctor if you have any of the following symptoms and they persist or become severe:

  • Difficulty controlling bowel movements
  • Loose, frequent stools
  • Oily or fatty stools
  • Oily spots on undergarments
  • Pain in the stomach or rectum
  • Passing gas more often
  • Urgent need to have a bowel movement

Also tell your doctor if the following symptoms occur and they become severe or do not go away: 

  • Anxiety
  • Changes in a woman's menstrual cycle
  • Headaches

 

Emergency Side Effects of Alli

Call your doctor or local emergency number immediately if you are taking either Alli or Xenical and develop any of these symptoms:

  • Difficulty breathing
  • Difficulty swallowing
  • Hives or itching
  • Stomach pain that is severe or does not go away  

Alli and Xenical have been linked to severe liver injury in a rare number of patients, mostly those who received the prescription-strength dosage. The most common side effects in those who developed liver damage were yellowing of the skin (jaundice), weakness, and stomach pain.

You should stop taking this drug and call your doctor immediately if you develop any of the following symptoms: 

  • Dark-colored urine
  • Fatigue
  • Fever
  • Light-colored stools
  • Loss of appetite
  • Severe, persistent itching
  • Weakness
  • Vomiting
  • Yellowing of the skin or eyes (jaundice)

These can be signs of liver damage.

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WebMD Medical Reference

Reviewed by Kimball Johnson, MD on October 13, 2012

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