Prescription Drug Information: Niacin (Page 2 of 6)

5.3 Liver Dysfunction

Cases of severe hepatic toxicity, including fulminant hepatic necrosis, have occurred in patients who have substituted sustained-release (modified-release, timed-release) niacin products for immediate-release (crystalline) niacin at equivalent doses.

Niacin extended-release should be used with caution in patients who consume substantial quantities of alcohol and/or have a past history of liver disease. Active liver diseases or unexplained transaminase elevations are contraindications to the use of niacin extended-release.

Niacin preparations have been associated with abnormal liver tests. In three placebo-controlled clinical trials involving titration to final daily niacin extended-release doses ranging from 500 to 3000 mg, 245 patients received niacin extended-release for a mean duration of 17 weeks. No patient with normal serum transaminase levels (AST, ALT) at baseline experienced elevations to more than 3 times the upper limit of normal (ULN) during treatment with niacin extended-release. In these studies, fewer than 1% (2/245) of niacin extended-release patients discontinued due to transaminase elevations greater than 2 times the ULN.

Liver-related tests should be performed on all patients during therapy with niacin extended-release. Serum transaminase levels, including AST and ALT (SGOT and SGPT), should be monitored before treatment begins, every 6 to 12 weeks for the first year, and periodically thereafter (e.g., at approximately 6-month intervals). Special attention should be paid to patients who develop elevated serum transaminase levels, and in these patients, measurements should be repeated promptly and then performed more frequently. If the transaminase levels show evidence of progression, particularly if they rise to 3 times ULN and are persistent, or if they are associated with symptoms of nausea, fever, and/or malaise, the drug should be discontinued.

5.4 Laboratory Abnormalities

Increase in Blood Glucose: Niacin treatment can increase fasting blood glucose. Frequent monitoring of blood glucose should be performed to ascertain that the drug is producing no adverse effects. Diabetic patients may experience a dose-related increase in glucose intolerance. Diabetic or potentially diabetic patients should be observed closely during treatment with niacin extended-release, particularly during the first few months of use or dose adjustment; adjustment of diet and/or hypoglycemic therapy may be necessary.

Reduction in platelet count: Niacin extended-release has been associated with small but statistically significant dose-related reductions in platelet count (mean of -11% with 2000 mg). Caution should be observed when niacin extended-release is administered concomitantly with anticoagulants; platelet counts should be monitored closely in such patients.

Increase in Prothrombin Time (PT): Niacin extended-release has been associated with small but statistically significant increases in prothrombin time (mean of approximately +4%); accordingly, patients undergoing surgery should be carefully evaluated. Caution should be observed when niacin extended-release is administered concomitantly with anticoagulants; prothrombin time should be monitored closely in such patients.

Increase in Uric Acid: Elevated uric acid levels have occurred with niacin therapy, therefore use with caution in patients predisposed to gout.

Decrease in Phosphorus: In placebo-controlled trials, niacin extended-release has been associated with small but statistically significant, dose-related reductions in phosphorus levels (mean of -13% with 2000 mg). Although these reductions were transient, phosphorus levels should be monitored periodically in patients at risk for hypophosphatemia.

6 ADVERSE REACTIONS

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

6.1 Clinical Studies Experience

In the placebo-controlled clinical trials database of 402 patients (age range 21 to 75 years, 33% women, 89% Caucasians, 7% Blacks, 3% Hispanics, 1% Asians) with a median treatment duration of 16 weeks, 16% of patients on niacin extended-release and 4% of patients on placebo discontinued due to adverse reactions. The most common adverse reactions in the group of patients treated with niacin extended-release that led to treatment discontinuation and occurred at a rate greater than placebo were flushing (6% vs. 0%), rash (2% vs. 0%), diarrhea (2% vs. 0%), nausea (1% vs. 0%), and vomiting (1% vs. 0%). The most commonly reported adverse reactions (incidence >5% and greater than placebo) in the niacin extended-release controlled clinical trial database of 402 patients were flushing, diarrhea, nausea, vomiting, increased cough and pruritus.

In the placebo-controlled clinical trials, flushing episodes (i.e., warmth, redness, itching and/or tingling) were the most common treatment-emergent adverse reactions (reported by as many as 88% of patients) for niacin extended-release. Spontaneous reports suggest that flushing may also be accompanied by symptoms of dizziness, tachycardia, palpitations, shortness of breath, sweating, burning sensation/skin burning sensation, chills, and/or edema, which in rare cases may lead to syncope. In pivotal studies, 6% (14/245) of niacin extended-release patients discontinued due to flushing. In comparisons of immediate-release (IR) niacin and niacin extended-release tablets, although the proportion of patients who flushed was similar, fewer flushing episodes were reported by patients who received niacin extended-release. Following 4 weeks of maintenance therapy at daily doses of 1500 mg, the incidence of flushing over the 4-week period averaged 8.6 events per patient for IR niacin versus 1.9 following niacin extended-release.

Other adverse reactions occurring in ≥5% of patients treated with niacin extended-release and at an incidence greater than placebo are shown in Table 2 below.

Table 2. Treatment-Emergent Adverse Reactions by Dose Level in ≥ 5% of Patients and at an Incidence Greater than Placebo; Regardless of Causality Assessment in Placebo-Controlled Clinical Trials

Placebo-Controlled Studies Niacin Extended-release Treatment @

Recommended Daily Maintenance Doses

Placebo

(n = 157)

500 mg

(n = 87)

1000 mg

(n = 110)

1500 mg (n = 136)

2000 mg

(n = 95)

%

%

%

%

%

Gastrointestinal Disorders

Diarrhea

13

7

10

10

14

Nausea

7

5

6

4

11

Vomiting

4

0

2

4

9

Respiratory

Cough, Increased

6

3

2

< 2

8

Skin and Subcutaneous Tissue Disorders

Pruritus

2

8

0

3

0

Rash

0

5

5

5

0

Vascular Disorders

Flushing &

19

68

69

63

55

Note: Percentages are calculated from the total number of patients in each column.

Adverse reactions are reported at the initial dose where they occur.

@ Pooled results from placebo-controlled studies; for niacin extended-release, n = 245 and median treatment duration = 16 weeks. Number of niacin patients (n) are not additive across doses.

The 500 mg/day dose is outside the recommended daily maintenance dosing range [see Dosage and Administration (2)] .

& 10 patients discontinued before receiving 500 mg, therefore they were not included.


In general, the incidence of adverse events was higher in women compared to men.

Atherothrombosis Intervention in Metabolic Syndrome with Low HDL/High Triglycerides:

Impact on Global Health Outcomes (AIM-HIGH)

In AIM-HIGH involving 3414 patients (mean age of 64 years, 15% women, 92% Caucasians, 34% with diabetes mellitus) with stable, previously diagnosed cardiovascular disease, all patients received simvastatin, 40 to 80 mg per day, plus ezetimibe 10 mg per day if needed, to maintain an LDL-C level of 40 to 80 mg/dL, and were randomized to receive niacin extended-release 1500 to 2000 mg/day (n=1718) or matching placebo (IR Niacin, 100 to 150 mg, n=1696). The incidence of the adverse reactions of “blood glucose increased” (6.4% vs. 4.5%) and “diabetes mellitus” (3.6% vs. 2.2%) was significantly higher in the simvastatin plus niacin extended-release group as compared to the simvastatin plus placebo group. There were 5 cases of rhabdomyolysis reported, 4 (0.2%) in the simvastatin plus niacin extended-release group and one (<0.1%) in the simvastatin plus placebo group [see Warnings and Precautions (5.1)] .

RxDrugLabels.com provides trustworthy package insert and label information about marketed prescription drugs as submitted by manufacturers to the U.S. Food and Drug Administration. Package information is not reviewed or updated separately by RxDrugLabels.com. Every individual prescription drug label and package insert entry contains a unique identifier which can be used to secure further details directly from the U.S. National Institutes of Health and/or the FDA.

As a leading independent provider of trustworthy medication information, we source our database directly from the FDA's central repository of drug labels and package inserts under the Structured Product Labeling standard. RxDrugLabels.com provides the full prescription-only subset of the FDA's repository. Medication information provided here is not intended as a substitute for direct consultation with a qualified health professional.

Terms of Use | Copyright © 2021. All Rights Reserved.