Note: This document contains side effect information about orlistat. Some of the dosage forms listed on this page may not apply to the brand name Alli.
Common side effects of Alli include: bowel urgency, frequent bowel movements, oily evacuation, oily rectal leakage, steatorrhea, and flatulence with discharge. Other side effects include: fecal incontinence. See below for a comprehensive list of adverse effects.
Applies to orlistat: oral capsule
Along with its needed effects, orlistat (the active ingredient contained in Alli) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur while taking orlistat:
Incidence not known
Some side effects of orlistat may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Applies to orlistat: oral capsule
The most commonly reported adverse events have included oily spotting, flatus with discharge, fecal urgency fatty/oily stool, oily evacuation, increased defecation and fecal incontinence.
Very common (10% or more): Oily spotting (up to 26.6%), flatus with discharge (up to 23.9%), fecal urgency (up to 22.1%), fatty/oily stool (up to 20%), oily evacuation (up to 11.9%), increased defecation (up to 10.8%), abdominal pain/discomfort (up to 25.5%)
Common (1% to 10%): Fecal incontinence, nausea, infectious diarrhea, rectal pain/discomfort, tooth disorder, gingival disorder, vomiting
Frequency not reported: Abdominal distention
Postmarketing reports: Pancreatitis, lower gastrointestinal bleeding
Gastrointestinal events usually occur within the first 3 months. Approximately 50% of all GI events lasted for less than 1 week with a majority lasting no more than 4 weeks. Although, in some individuals, gastrointestinal events have lasted 6 months or more. In clinical trials, gastrointestinal adverse effects were the most common reason for treatment discontinuation.
Reports of hepatic failure have been received during postmarketing surveillance, with some of these cases resulting in liver transplant or death. Rare cases of increased transaminases, alkaline phosphatase, and hepatitis have been received.
Postmarketing reports: Increases in hepatic transaminases, alkaline phosphatase elevations, hepatitis, hepatic failure, liver transplant
Postmarketing reports: Hypersensitivity reactions including pruritus, rash, urticaria, angioedema, bronchospasm, and anaphylaxis; at least one case of cutaneous leukocytoclastic vasculitis
Frequency not reported: Hypoglycemia, at least one case of diabetic ketoacidosis; polyuria, polydipsia
Cases of leukocytoclastic vasculitis have been reported during the postmarketing period. Clinical signs include palpable purpura, maculopapular lesions, or bullous eruption.
Postmarketing reports: Bullous eruption, leukocytoclastic vasculitis
Postmarketing reports: Acute oxalate nephropathy
Convulsions have been reported in patients concomitantly receiving this drug with antiepileptic drugs.
Very common (10% or more): Headache (up to 30.6%)
Common (1% to 10%): Dizziness
Postmarketing reports: Convulsions
Common (1% to 10%): Sleep disorder, anxiety, depression
Very common (10% or more): Influenza (up to 39.7%), upper respiratory infection (up to 38.1%)
Common (1% to 10%): Lower respiratory infection, ear, nose & throat symptoms
Very common (10% or more): Back pain (up to 13.9%)
Common (1% to 10%): Arthritis, myalgia, joint disorder, tendonitis
Common (1% to 10%): Menstrual irregularity, vaginitis, urinary tract infection
Common (1% to 10%): Pedal edema
Postmarketing reports: Decreased prothrombin, increased INR and unbalanced anticoagulant treatment
Decreased prothrombin and increased INR resulting in unbalanced anticoagulant treatment has been reported in patients treated concomitantly with anticoagulants.
Common (1% to 10%): Fatigue, otitis
Postmarketing reports: Hypothyroidism
For patients receiving levothyroxine, hypothyroidism has been reported requiring an adjustment to levothyroxine therapy.
Medically reviewed by BestRx Medical Team Last updated on 1/1/2020.
Source: Drugs.com Alli