Whenever vitamin B3 is taken in high doses, there are concerns regarding liver inflammation. Because of this, patients taking high-dose nicotinic acid (niacin) may undergo regular blood testing, specifically liver enzyme tests. Patients should also be aware of any signs or symptoms of liver inflammation, including jaundice (yellowing of the eyes and/or skin).

When patients first begin taking nicotinic acid, they may feel periods of dizziness or lightheadedness, especially when rising from a seated position or after lying down. Getting up slowly may help reduce this symptom. This side effect usually lessens after a few weeks, as the body become more accustomed to the medication.

Those taking extended-relief (or time-released) capsules should be careful not to crush, break or chew the capsules. Those having difficulty swallowing a capsule may mix the contents of the capsule into some jam or jelly and then swallow without chewing. People taking time-release tablets may break the tablet only if it is scored (dented to allow for easy breaking). Tablets must not be crushed or chewed before swallowing.

Patients should carefully follow the directions for taking their medication provided by their physician and pharmacy. Those who miss a dose of this medication should take it as soon as possible, unless it is nearly time for the next dose. In that case, the missed dose should be skipped. Double doses of this medication should not be taken.

Nicotinic acid may be less effective in people who are significantly overweight. Therefore, in addition to lifestyle changes recommended to reduce blood fat levels, patients may be placed on a weight loss program. In many cases, the lifestyle changes needed to manage blood fats will be similar to those in a weight loss program (e.g., diet, exercise, stress management).

All patients taking nicotinic acid should inform their physician immediately of any side effects or concerns. Patients should not abruptly stop taking their medications without first consulting their physicians. It is also important that patients notify all physicians (including dentists) that they are taking nicotinic acid before undergoing any surgical procedure.

Most patients on medication to treat high cholesterol (hypercholesterolemia) will take it for the rest of their lives, provided no serious side effects occur. Patients should remember that medications may control high cholesterol, but they do not cure it. Even if all their symptoms are relieved, patients should continue to take their medication exactly as directed, eat a heart-healthy diet that is low in saturated fats and keep all scheduled follow-up appointments with their physician.