Xenical side effects are more common during the first year of treatment, but as with many other rapid weight loss medications cannot really be anticipated. If any develop or change in intensity you should notify your physician immediately. Only your doctor can determine if it is safe to continue taking this medication if you experience these Xenical side effects.

Abdominal discomfort or pain, anxiety, arthritis, back pain, diarrhea, dizziness, earache, fatigue, fatty or oily stools, facial urgency or incontinence, flu, gas with fecal discharge, gum problems, headache, increased defecation, menstrual problems, muscle pain, nausea, oily discharge, rectal discomfort or pain, respiratory tract infections, skin rash, sleep problems, tooth problems, urinary tract infections, vaginal inflammation, vomiting

The Xenical side effects that usually occur after the first year of treatment with this weight loss drug include depression, leg pain, swollen feet, and tendonitis.

You should expect your weight loss to begin within two weeks and to continue for six to 12 months. The effect of using Xenical for weight loss for more than two years is still unknown. The Xenical side effects such as diarrhea and abdominal pain may become worse if you continue eating a high-fat diet or even consume a high-fat meal. You should always limit your fat intake as much as possible.

Your doctor should test your thyroid function before starting you on Xenical to make sure that your weight problem is not due to an underactive thyroid gland (hypothyroidism). Xenical is not believed to be an appropriate remedy for this problem.

Another problematic Xenical side effect is that it may potentially increase the likelihood of kidney stones. You should use Xenical with caution if you have a history of kidney problems.

If you have a history of diabetes, weight loss is likely to reduce your blood sugar levels. If you’re taking oral diabetes medication such as insulin, your dose may have to be reduced while on this weight loss drug. Also, you should note that the safety and efficacy of this drug in children younger than 12 years old has never been established.

If this weight loss medication is taken with certain other drugs, the effects of either can be increased, decreased or otherwise altered. It is especially important to check with your physician before combining Xenical with either of the following medications:

Cyclosporine (Neoral, Sandimmune)

Warfarin (Coumadin)

The effects of Xenical have not been adequately determined on women who are pregnant. If you’re pregnant or planning to become pregnant, you should inform your doctor immediately. It is not known currently whether Xenical appears in breast milk. Do not take it if you are breast-feeding.

Some Information From The PDR Pocket Guide to Prescription Drugs