• Avoid prescribing nicotinic acid in people with:
• Significant hepatic dysfunction.
• Active peptic ulcer disease.
• Arterial bleeding.
• Precautions:
• Nicotinic acid should be prescribed with caution in people who consume substantial quantities of alcohol or who have a history of liver disease.
• Treatment has been associated with abnormal liver function tests:
• Elevated liver transaminases have been observed with nicotinic acid modified-release tablets (Niaspan^®). Transaminase elevations were reversible upon discontinuation of therapy.
• Stop treatment if there is evidence of a progressive increase in transaminase levels, particularly if they rise to three times the upper limit of normal.
• The manufacturer of Niaspan^® advises caution when prescribing nicotinic acid to:
• People with diabetes or at high risk of diabetes, as there may be a dose-related increase in glucose intolerance. Adjustment of diet, oral antihyperglycaemics, and insulin therapy may be necessary.
• People with unstable angina or in the acute phase of myocardial infarction, particularly when they are also receiving vasoactive drugs such as nitrates, calcium-channel blockers, or adrenergic blocking agents.
• People undergoing surgery, as nicotinic acid may affect platelet count and prothrombin time.
• People on anticoagulants (closer monitoring of prothrombin time and platelet count are recommended).
• People predisposed to gout, as elevated uric acid levels have been reported with nicotinic acid therapy.

[ABPI Medicines Compendium, 2006a]