There are multiple interactions reported between these two agents.

Interaction Details

Testosterone Undecanoate is classified as belonging to the following category: Hepatotoxic Drugs

Theoretically, concomitant use of niacin and hepatotoxic drugs might increase the risk of hepatotoxicity.
Niacin has been associated with cases of liver toxicity, especially when used in pharmacologic doses. Sustained-release niacin preparations appear to be associated with a higher risk of hepatotoxicity than immediate-release niacin.

Interaction Rating

Moderate

Likelihood of Occurrence

Possible

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists

References

  • American Society of Health-System Pharmacists. ASHP Therapeutic Position Statement on the safe use of niacin in the management of dyslipidemias. Am J Health Syst Pharm 1997;54:2815-9.
  • Bays HE, Dujovne CA. Drug interactions of lipid-altering drugs. Drug Saf 1998;19:355-71.
  • Rader JI, Calvert RJ, Hathcock JN. Hepatic toxicity of unmodified and time-release preparations of niacin. Am J Med 1992;92:77-81.
  • Etchason JA, Miller TD, Squires RW, et al. Niacin-induced hepatitis: a potential side effect with low-dose time-release niacin. Mayo Clin Proc. 1991;66(1):23-8.
  • Henkin Y, Johnson KC, Segrest JP. Rechallenge with crystalline niacin after drug-induced hepatitis from sustained-release niacin. JAMA. 1990;264(2):241-3.
  • Henkin Y, Oberman A, Hurst DC, Segrest JP. Niacin revisited: clinical observations on an important but underutilized drug. Am J Med. 1991;91(3):239-46.
  • Bassan M. A case for immediate-release niacin. Heart Lung. 2012 Jan-Feb;41(1):95-8.

Interaction Details

Testosterone Undecanoate is classified as belonging to the following category: Thyroid Hormone

Theoretically, niacin might antagonize the therapeutic effects of thyroid hormones.
Clinical research and case reports suggests that taking niacin can reduce serum levels of thyroxine-binding globulin by up to 25% and moderately reduce levels of thyroxine (T4). Patients taking thyroid hormone for hypothyroidism might need dose adjustments when using niacin.

Interaction Rating

Moderate

Likelihood of Occurrence

Probable

Interaction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.

References

  • O'Brien T, Silverberg JD, Nguyen TT. Nicotinic acid-induced toxicity associated with cytopenia and decreased levels of thyroxine-binding globulin. Mayo Clin Proc. 1992;67(5):465-8.
  • Cashin-Hemphill L, Spencer CA, Nicoloff JT, et al. Alterations in serum thyroid hormonal indices with colestipol-niacin therapy. Ann Intern Med. 1987;107(3):324-9.
  • Drinka PJ. Alterations in thyroid and hepatic function tests associated with preparations of sustained-release niacin. Mayo Clin Proc. 1992;67(12):1206.
  • Shakir KM, Kroll S, Aprill BS, Drake AJ 3rd, Eisold JF. Nicotinic acid decreases serum thyroid hormone levels while maintaining a euthyroid state. Mayo Clin Proc. 1995;70(6):556-8.

Niacin Overview

Niacin Niacin, also known as vitamin B3, is a water-soluble vitamin found in a variety of foods, including meat, poultry, fish, and fortified grains. It plays a variety of roles in the body, including in the metabolism of carbohydrates, fats, and proteins. It is also necessary for the production of energy in the body and in the synthesis of different hormones. Niacin deficiency is rare in developed countries, however, supplementation has been shown to have several positive benefits. For example, it can reduce the risk of diabetic neuropathy (i.e., nerve pain) and has been shown effective for treating some types of high cholesterol (extended-release niacin is used as a prescription drug in the United States for this purpose). There is a multitude of niacin forms available as dietary supplements, including NADH, niacinamide, and nicotinamide riboside, all with different properties.
See More Information Regarding Niacin

Testosterone Undecanoate Overview

  • Testosterone cypionate (Depo-Testosterone), testosterone enanthate (Xyosted, available generically), testosterone undecanoate (Aveed), and testosterone pellet (Testopel) are forms of testosterone injection used to treat symptoms of low testosterone in men who have hypogonadism (a condition in which the body does not produce enough natural testosterone). Testosterone is used only for men with low testosterone levels caused by certain medical conditions, including disorders of the testicles, pituitary gland (a small gland in the brain), or hypothalamus (a part of the brain) that cause hypogonadism. Your doctor will order certain lab tests to check your testosterone levels to see if they are low before you begin to use testosterone injection. Testosterone enanthate (available generically) and testosterone pellet (Testopel) are also used to stimulate puberty in males with delayed puberty. Testosterone enanthate (available generically) injection may be used in certain women with a type of breast cancer called mammary cancer that has spread to other parts of the body. Testosterone should not be used to treat the symptoms of low testosterone in men who have low testosterone due to aging ('age related hypogonadism'). Testosterone is in a class of medications called androgenic hormones. Testosterone is a hormone produced by the body that contributes to the growth, development, and functioning of the male sexual organs and typical male characteristics. Testosterone injection works by supplying synthetic testosterone to replace the testosterone that is normally produced naturally in the body. When used to treat breast cancer, testosterone works by stopping the release of estrogen.

See More Information Regarding Testosterone Injection

Niacin - More Interactions

Niacin interacts with 694 drugs

Interaction Rating Key

These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.

Major The combined use of these agents is strongly discouraged as serious side effects or other negative outcomes could occur.
Moderate Use cautiously under the care of a healthcare professional or avoid this combination. A significant interaction or negative outcome could occur.
Minor Be aware that there is a chance of an interaction. Watch for warning signs of a potential interaction.
Unknown No interactions have been reported or no interaction data is currently available.

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Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

Drug descriptions are provided by MedlinePlus.

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