Clinical Studies Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.

The following table summarizes the adverse reactions observed in two placebo-controlled clinical trials.

In a randomized, cross-over study in sixty PBC patients, seven patients (11.6%) reported nine adverse reactions: abdominal pain and asthenia (1 patient), nausea (3 patients), dyspepsia (2 patients) and anorexia and esophagitis (1 patient each). One patient on the twice a day regimen (total dose 1000 mg) withdrew due to nausea. All of these nine adverse reactions except esophagitis were observed with the twice a day regimen at a total daily dose of 1000 mg or greater. However, an adverse reaction may occur at any dose.

Postmarketing Experience

The following adverse reactions, presented by system organ class in alphabetical order, have been identified during postapproval use of urso (ursodiol) diol. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

• Gastrointestinal disorders: abdominal discomfort, abdominal pain, constipation, diarrhea, dyspepsia, nausea, vomiting.
• General disorders and administration site conditions: malaise, peripheral edema, pyrexia.
• Immune System Disorders: Drug hypersensitivity to include facial edema, urticaria, angioedema and laryngeal edema.
• Musculoskeletal and connective tissue disorders: myalgia
• Nervous system disorders: dizziness, headache.
• Respiratory, thoracic and mediastinal disorders: cough.
• Skin and subcutaneous tissue disorder: alopecia, pruritus, rash.

Read the Urso (ursodiol) Side Effects Center for a complete guide to possible side effects »

Bile Acid Sequestering Agents

Bile acid sequestering agents such as cholestyramine and colestipol may interfere with the action of URSO 250 (urso (ursodiol) diol) and URSO (ursodiol) Forte by reducing its absorption.

Aluminum-based Antacids

Aluminum-based antacids have been shown to adsorb bile acids in vitro and may be expected to interfere with URSO 250 (urso (ursodiol) diol) and URSO (ursodiol) Forte in the same manner as the bile acid sequestering agents.

Drugs Affecting Lipid Metabolism

Estrogens, oral contraceptives, and clofibrate (and perhaps other lipid-lowering drugs) increase hepatic cholesterol secretion and encourage cholesterol gallstone formation and hence may counteract the effectiveness of URSO 250 (urso (ursodiol) diol) and URSO (ursodiol) Forte.

Last reviewed on RxList: 12/28/2009
This monograph has been modified to include the generic and brand name in many instances.