Niacin (niacin)

No dosing information is available for this tab.

Niacin and niacinamide are administered orally.

Niacin reportedly potentiates the hypotensive effect of ganglionic blocking drugs.

Long-term administration of isoniazid may interfere with the conversion of dietary tryptophan to niacin and increase the requirement of niacin.

There are no contraindication interactions for this drug.

Severe Interaction: Action is required to reduce the risk of severe adverse interaction.

Niacin (>= 250 MG)/Hmg-Coa Reductase Inhibitors

SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction.

MECHANISM OF ACTION: Unknown.

CLINICAL EFFECTS: Myopathy and rhabdomyolysis (muscle aches, tenderness, and weakness) have been associated with concomitant administration of HMG-CoA reductase inhibitors and niacin.

PREDISPOSING FACTORS: The risk for myopathy or rhabdomyolysis may be greater in patients 65 years and older, inadequately treated hypothyroidism, renal impairment, carnitine deficiency, malignant hyperthermia, or in patients with a history of myopathy or rhabdomyolysis. Patients with a SLCO1B1 polymorphism that leads to decreased function of the hepatic uptake transporter OATP1B1 may have increased statin concentrations and be predisposed to myopathy or rhabdomyolysis. Patients on rosuvastatin with ABCG2 polymorphisms leading to decreased or poor BCRP transporter function may have increased rosuvastatin concentrations and risk of myopathy.

PATIENT MANAGEMENT: The benefit of further alterations in lipid levels with combined use of statins and lipid-lowering dosages of niacin (<= 1000 mg/day) should be carefully weighed against the potential risks.(1-10) The US manufacturer of simvastatin states that dosages of niacin should not exceed 1000 mg daily in patients of Chinese descent.(6)

DISCUSSION: The risk of myopathy is increased during concurrent use of HMG-CoA reductase inhibitors and niacin.(1-10) Concomitant administration of niacin with the immediate release formulation of fluvastatin had no effect on fluvastatin pharmacokinetics. Myopathy was not observed in a trial of concurrent fluvastatin and niacin in 74 patients. Concurrent fluvastatin and niacin results in additive effects on total cholesterol and LDL cholesterol.(9) In uncontrolled studies, most subjects who developed myopathy while on lovastatin were also taking cyclosporine, gemfibrozil, or niacin.(1) However, a systematic review showed comparable rates of adverse event reports (AERs) including serious adverse events, hepatotoxicity, or rhabdomyolysis for the combination of lovastatin with niacin-extended release (ER) pill relative to either agent alone or to other statins. Therefore, these results did not support a clinically significant adverse drug interaction between niacin-ER and statins.(14) In clinical trials involving small numbers of patients, no myopathy was reported with concurrent pravastatin and niacin.(10) There are case reports of myopathy during concurrent lovastatin and niacin.(2,11,12) Interim HPS2 results showed a higher rate of myopathy in patients of Chinese descent (0.43%) when compared to patients of non-Chinese descent (0.03%) in patients taking simvastatin (40 mg) with cholesterol-lowering doses of niacin.(7) Kosoglou suggests that there is a small pharmacokinetic drug interaction between ER niacin and ezetimibe/simvastatin but is not clinically significant.(15) However, the HPS2-THRIVE showed a significant four-fold excess risk of myopathy with the addition of ER niacin 2g plus laropiprant 40mg daily (ERN/LRPT) to simvastatin 40mg daily (with or without ezetimibe 10mg daily). This additional risk is particularly prevalent among Chinese descent versus European descent.(16) The AIM-HIGH trial randomized 3414 patients to receive niacin extended-release 1500-2000 mg per day or placebo in addition to current therapy of simvastatin 40-80 mg per day and ezetimibe 10 mg per day if needed to achieve a goal LDL of 40-80 mg/dL. Patients were followed for a mean of 3 years. The primary efficacy endpoint of composite of the first event of death from coronary heart disease, nonfatal myocardial infarction, ischemic stroke, hospitalization (greater than 23 hours) for an acute coronary syndrome, or symptom-driven coronary or cerebral vascularization, occurred in 16.4% of patients in the niacin group and 16.2% of patients in the placebo group (p=0.80).(17) The HPS2-THRIVE trial randomized 25,673 patients to receive extended-release niacin 2000 mg with laropiprant 40 mg per day or placebo in addition to current therapy of simvastatin 40 mg per day. Patients were followed for a median of 3.9 years. The primary efficacy endpoint of first major vascular event, defined as a major coronary event (nonfatal myocardial infarction or death from coronary causes), stroke of any type, or coronary or noncoronary vascularization, occurred in 13.2% of patients in the niacin-laropiprant group and 13.7% of patients in the placebo group (p=0.29).(18) A post-hoc analysis of the AIM-HIGH trial showed significant lowering of triglycerides (59 mg/dL) in the extended-release niacin (ERN) group compared to the placebo group (20mg/dL). High density lipoprotein levels showed improvement in the ERN group compared to the placebo (11.3mg/dL vs. 4.7 mg/dL, respectively). The incidence of cardiovascular disease events was similar in both groups. However, all-cause mortality was significantly higher in the ERN group (15.4%) versus the control group (9.2%).(19) A meta-analysis investigating the effects of niacin for primary and secondary prevention of cardiovascular events suggests that niacin does not reduce mortality or rates of myocardial infarctions or strokes. Increased side effects are reported with niacin. Benefits from niacin therapy in the prevention of cardiovascular disease events are unlikely.(20) The AIM HIGH trial investigated the effects of ERN added to simvastatin/ezetimibe on glucose and insulin values. ERN increased fasting glucose from baseline to 1 year in patients with normal (7.9 vs 4.3 mg/dL, respectively) and impaired fasting glucose (4.1 vs 1.4 mg/dL, respectively). There was an increased risk of progressing from normal to impaired fasting glucose in the ERN (58.6% cases) versus placebo (41.5% cases).(21) One or more of the drug pairs linked to this monograph have been included in a list of interactions that could be considered for classification as "non-interruptive" in EHR systems. This DDI subset was vetted by an expert panel commissioned by the U.S. Office of the National Coordinator (ONC) for Health Information Technology.

There are no moderate interactions for this drug.

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• Arterial hemorrhage
• Disease of liver

• Alcohol use disorder
• Invasive surgical procedure
• Peptic ulcer

• 30 day risk period post-myocardial infarction
• Diabetes mellitus
• Disease of liver
• Gout
• Hypophosphatemia
• Hypotension
• Increased risk of bleeding due to coagulation disorder
• Unstable angina pectoris

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Rare or Very Rare

• Abnormal hepatic function tests
• Anaphylaxis
• Angioedema
• Atrial fibrillation
• Drug-induced hepatitis
• Dyspnea
• Edema
• Jaundice
• Laryngeal edema
• Laryngismus
• Macular retinal edema
• Myopathy
• Paresthesia
• Peptic ulcer
• Urticaria
• Vesicular rash

More Frequent

• Cough
• Diarrhea
• Dyspepsia
• Flushing
• Nausea
• Pruritus of skin
• Vomiting

Less Frequent

• Cardiac arrhythmia
• Cardiac arrhythmia
• Diarrhea
• Dizziness
• Dizziness
• Dry eye
• Dry skin
• Dry skin
• Exacerbation of peptic ulcer
• Exacerbation of peptic ulcer
• Flushing
• Headache disorder
• Hyperglycemia
• Hyperglycemia
• Hyperuricemia
• Hyperuricemia
• Hypophosphatemia
• Myalgia
• Myalgia
• Nausea
• Pruritus of skin
• Syncope
• Syncope
• Vomiting

Rare or Very Rare

• Acquired acanthosis nigricans
• Blurred vision
• Chills
• Dyschromia
• Eructation
• Facial edema
• Flatulence
• General weakness
• Hyperhidrosis
• Hypoprothrombinemia
• Hypotension
• Insomnia
• Maculopapular rash
• Migraine
• Muscle weakness
• Nervousness
• Orthostatic hypotension
• Palpitations
• Peripheral edema
• Skin rash
• Stinging of skin
• Tachycardia
• Thrombocytopenic disorder

No enhanced messaging available.

No enhanced messaging available.

Administration of supplementary doses of niacin during pregnancy has not been associated with any adverse effects to the mother or fetus. However, toxicologic studies have not been performed with large doses of niacin, and large doses of the drug should not be used in women who are or may become pregnant unless the possible benefits outweigh the potential risks to the fetus.

Administration of supplementary doses of niacin during lactation has not been associated with any adverse effects to the mother or fetus.

No enhanced messaging available.