Xenical Adverse Reactions

Clinical trials: Adverse reactions to Orlistat (Xenical) are largely gastrointestinal in nature and related to the pharmacologic effect of the drug on preventing the absorption of ingested fat. Commonly observed events are oily spotting, flatus with discharge, fecal urgency, fatty/oily stool, oily evacuation, increased defecation and fecal incontinence. The incidence of these increases the higher the fat content of the diet. Patients should be counselled as to the possibility of gastrointestinal effects occurring and how best to handle them such as reinforcing the diet, particularly the percentage of fat it contains. Consumption of a diet low in fat will decrease the likelihood of experiencing adverse gastrointestinal events and this may help patients monitor and regulate their fat intake.
These adverse gastrointestinal reactions are generally mild and transient. They occurred early in treatment (within 3 months) and most patients experienced only one episode.
Treatment-emergent GI-adverse events that occurred commonly among patients treated with Orlistat (Xenical) were: abdominal pain/discomfort, flatulence, liquid stools, soft stools, rectal pain/discomfort, tooth disorder, gingival disorder.
Other events observed rarely were: upper respiratory infection, lower respiratory infection; influenza; headache; menstrual irregularity; anxiety; fatigue; urinary tract infection.
Unique treatment adverse events observed in obese type 2 diabetic patients were hypoglycemia (very common) and abdominal distension (common). Weight loss induced by Orlistat (Xenical) is accompanied by improved metabolic control in type 2 diabetics which might allow or require reduction in the dose of hypoglycemic medication (see Precautions).
In a 4-year clinical trial, the general pattern of adverse event distribution was similar to that reported for the 1 and 2 year studies with the total incidence of gastrointestinal related adverse events occurring in year 1 decreasing year on year over the four year period.
Post-Marketing: Rare cases of hypersensitivity have been reported. Main clinical symptoms are pruritus, rash, urticaria, angioedema, bronchspasm and anaphylaxis.
Very rare cases of bullous eruption, increase in liver transaminases and in alkaline phosphatase and exceptional cases of severe liver injury resulting in liver transplant or death, have been reported. No causal relationship or physiopathological mechanism between liver injury and orlistat therapy has been established.
Reports of decreased prothrombin, increased INR and unbalanced anticoagulant treatment resulting in change of hemostatic parameters have been reported in patients treated concomitantly with orlistat and anticoagulants during post-marketing (see Interactions).
Convulsions have been reported in patients treated concomitantly with orlistat and antiepileptic drugs (see Interactions).
Cases of hyperoxaluria and oxalate nephropathy have been reported.