Also indexed as: Actimmune, Alferon N, Avonex, Betaseron,
Infergen, Intron, Rebif, Roferon-A, Wellferon
Interferons are proteins made by the human
immune system for fighting viral
infections and regulating cell function. Three types of interferons are used as drugs:
interferon alpha, interferon beta, and interferon gamma. They are used by injection to treat
viral infections, hepatitis, multiple sclerosis, some cancers, and other diseases.
The information in this article pertains to interferon in general. The interactions
reported here may not apply to all the Also Indexed As terms. Talk to your doctor or
pharmacist if you are taking any of these drugs.
Summary of
Interactions with Vitamins, Herbs, and Foods
In some cases, an herb or supplement may appear in more than one category, which may seem
contradictory. For clarification, read the full article for details about the summarized
interactions.
 May Be Beneficial: Side effect
reduction/prevention—Taking these supplements may help reduce the likelihood and/or
severity of a potential side effect caused by the medication. |
Thymus peptides*
|
| May Be Beneficial: Supportive
interaction—Taking these supplements may support or otherwise help your medication
work better. |
Licorice*
N-acetyl cysteine (NAC)*
Thymus peptides*
|
Avoid: Reduced drug absorption/bioavailability—Avoid these supplements
when taking this medication since the supplement may decrease the absorption and/or activity
of the medication in the body. |
Thymus peptides*
|
|
Avoid: Adverse interaction—Avoid these supplements when taking this
medication because taking them together may cause undesirable or dangerous results. |
Bupleurum
|
| Depletion or interference |
None known
|
An asterisk (*) next to an item in the summary indicates that the
interaction is supported only by weak, fragmentary, and/or contradictory scientific
evidence.
Interactions with Dietary Supplements
N-acetyl cysteine
(NAC)
One preliminary trial found that adding 600 mg NAC three times per day to interferon therapy
for people with chronic hepatitis C led to
improvement in their conditions not seen with interferon alone.1 However, other
preliminary2 3 and double-blind trials4 5 have
failed to confirm the efficacy of this approach. At the present time, sufficient evidence is
lacking to support the use of this drug-nutrient combination in persons with hepatitis.
Thymus
peptides
Peptides or short proteins derived from the immune organ known as the thymus gland have been
investigated in combination with interferon therapy for people with hepatitis B and C. One
study found that adding thymus humoral factor-gamma 2 to interferon therapy prevented
decreases in white blood cell counts sometimes seen with interferon alone, and also seemed to
improve the efficacy of interferon against hepatitis B.6 Thymus humoral
factor-gamma 2 must be administered by injection, requiring consultation with a doctor. It is
not known whether orally administered thymus extracts would be useful in combination with
interferon.
Interactions with Herbs
Bupleurum (Bupleurum chinense)
Bupleurum is the major constituent of a Japanese Kampo (herbal) medicine formula called
sho-saiko-to. This formula has been used alone or with interferon to treat hepatitis. Eighty or more cases of drug-induced
pneumonitis (inflammation of the lungs) have been associated with the use of sho-saiko-to
alone or with interferon.7 8 9 10 Until more is
known, sho-saiko-to should not be combined with interferon.
Licorice (Glycyrrhiza glabra)
Injections of the licorice compound glycyrrhizin are commonly used to treat hepatitis in
Japan. The combination of glycyrrhizin and interferon may be more effective than interferon
alone.11 12 Injectable glycyrrhizin is available from some physicians.
So far, human studies have not used orally administered licorice extracts in
conjunction with interferon.
References:1. Beloqui O, Prieto J, Sua’rez B, et al. N-Acetyl cysteine
enhances the response to interferon-alpha in chronic hepatitis C: A pilot study. J
Interferon Res 1993;13:279–82.
2. Look MP, Gerard A, Rao GS, et al. Interferon/antioxidant combination
therapy for chronic hepatitis C--a controlled pilot trial. Antiviral Res
1999;43:113–22.
3. Cimino L, Belisario MA, Intrieri M, et al. Effect of N-acetyl-cysteine
on lymphomonocyte glutathione and response to interferon treatment in C-virus chronic
hepatitis. Ital J Gastroenterol Hepatol 1998;30:189–93.
4. Grant PR, Black A, Garcia N, et al. Combination therapy with
interferon-alpha plus N-acetyl cysteine for chronic hepatitis C: a placebo controlled
double-blind multicentre study. J Med Virol 2000;61:439–42.
5. Ideo G, Bellobuono A, Tempini S, et al. Antioxidant drugs combined
with alpha-interferon in chronic hepatitis C not responsive to alpha-interferon alone: a
randomized, multicentre study. Eur J Gastroenterol Hepatol 1999;11:1203–7.
6. Farhat BA, Marinos G, Daniels HM, et al. Evaluation of efficacy and
safety of thymus humoral factor-gamma 2 in the management of chronic hepatitis B. J
Hepatol 1995;23:21–7.
7. Nakagawa A, Yamaguchi I, Takao T, Amano H. Five cases of drug-induced
pneumonitis due to sho-saiko-to or interferon alpha or both. Nippon Kyobu Shikkan Gakkai
Zasshi 1995;33:1361–6 [in Japanese].
8. Ishizaki T, Sasaki F, Ameshima S, et al. Pneumonitis during interferon
and/or herbal drug therapy in patients with chronic active hepatitis. Eur Respir J
1996;9:2691–6.
9. Sugiyama H, Nagai M, Kotajima F, et al. A case of interstitial
pneumonia with chronic hepatitis C following interferon-alpha and sho-saiko-to therapy.
Arerugi 1995;44:711–4 [in Japanese].
10. Sato A, Toyoshima M, Kondo A, et al. Pneumonitis induced by the
herbal medicine Sho-saiko-to in Japan. Nippon Kyobu Shikkan Gakkai Zasshi
1997;35:391–5 [in Japanese].
11. Fujisawa K. Interferon therapy in hepatitis C virus (HCV) induced
chronic hepatitis: Clinical significance of pretreatment with glycyrhizine. Trop
Gastroenterol 1991;12:176–9.
12. Abe Y, Ueda T, Kato T, et al. Effectiveness of interferon,
glycyrrhizin combination therapy in patients with chronic hepatitis C. Nippon Rinsho
1994;52:1817–22 [in Japanese].