Drug & supplement interaction

Transfer Factor + Interferon Alfa-2b

Interferon Alfa-2b brand names: Rebetron, Intron A, Viraferon.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Transfer Factor and Interferon Alfa-2b in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first.

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Interaction report

Transfer Factor and Interferon Alfa-2b

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Interferon Alfa-2b and Transfer Factor in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

Worth understanding: our licensed dataset holds no drug-interaction record for Transfer Factor at all — not against Interferon Alfa-2b, and not against any other medication we track. This verdict therefore rests on the absence of any recorded data, not on research that looked at this combination and found nothing. We cannot rule an interaction out.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Transfer Factor safety at a glance

Transfer Factor overall Use caution Generally well tolerated in studies, but long-term safety and product quality are not well established.
Pregnancy Avoid Safety has not been established, so it is best avoided during pregnancy.
Breastfeeding Avoid Not enough safety information exists, so avoid while breastfeeding.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Interferon Alfa-2b and Transfer Factor? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

What Transfer Factor Itself Has Been Linked To

This is not an interaction — nothing below involves Interferon Alfa-2b. It is the side-effect record for Transfer Factor on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Transfer Factor, this list is the first place to look.

  • Acne Additional detail

    “Orally or parenterally, transfer factor seems to be well tolerated. Adverse effects may include fever. Parenterally, transfer factor can cause nausea, fatigue, and tenderness, pain, and swelling at the injection site.”

    Transfer Factor · Natural Medicines adverse-effect record, reported in acne.

    6 sources cited
    1. 350. Jones JF, Minnich LL, Jeter WS, et al. Treatment of childhood combined Epstein-Barr virus/cytomegalovirus infection with oral bovine transfer factor. Lancet 1981;2:122-4. PubMed
    2. 1445. Louie E, Borkowsky W, Klesius PH, et al. Treatment of cryptosporidiosis with oral bovine transfer factor. Clin Immunol Immunopathol 1987;44:329-34. PubMed
    3. 1507. Fudenberg HH. Transfer factor: past, present and future. Annu Rev Pharmacol Toxicol 1989;29:475-516. PubMed
    4. 3062. Miller LL, Spitler LE, Allen RE, Minor DR. A randomized, double-blind, placebo-controlled trial of transfer factor as adjuvant therapy for malignant melanoma. Cancer 1988;61:1543-9. PubMed
    5. 3063. Bukowski RM, Deodhar S, Hewlett JS, Greenstreet R. Randomized controlled trial of transfer factor in Stage II malignant melanoma. Cancer 1983;51:269-72. PubMed
    6. 7562. Lloyd AR, Hickie I, Brockman A, et al. Immunologic and psychologic therapy for patients with chronic fatigue syndrome: a double-blind, placebo-controlled trial. Am J Med 1993;94:197-203. PubMed

    “Orally, transfer factor may cause severe acne in some patients.”

    Transfer Factor · Natural Medicines adverse-effect record, reported in acne.

    1 source cited
    1. 78820. De Vinci, C., Levine, P. H., Pizza, G., Fudenberg, H. H., Orens, P., Pearson, G., and Viza, D. Lessons from a pilot study of transfer factor in chronic fatigue syndrome. Biotherapy 1996;9(1-3):87-90. PubMed
  • Fever Additional detail

    “Orally or parenterally, transfer factor may cause fever.

    There is some concern that bovine-derived transfer factor that is produced from cows in countries where bovine spongiform encephalitis (BSE) has been reported might be contaminated with diseased tissue. Countries where BSE has been reported include Great Britain, France, the Netherlands, Portugal, Luxembourg, Ireland, Switzerland, Oman, and Belgium.”

    Transfer Factor · Natural Medicines adverse-effect record, reported in encephalitis.

    4 sources cited
    1. 1507. Fudenberg HH. Transfer factor: past, present and future. Annu Rev Pharmacol Toxicol 1989;29:475-516. PubMed
    2. 78789. Thestrup-Pedersen, K., Grunnet, E., and Zachariae, H. Transfer factor therapy in mycosis fungoides: a double-blind study. Acta Derm.Venereol. 1982;62(1):47-53. DOI
    3. 78809. Fernandez, O., Diaz, N., Morales, E., Toledo, J., Hernandez, E., Rojas, S., Madriz, X., and Lopez, Saura P. Effect of transfer factor on myelosuppression and related morbidity induced by chemotherapy in acute leukaemias. Br.J.Haematol. 1993;84(3):423-427 PubMed
    4. 1825. Lewis CJ. Letter to reiterate certain public health and safety concerns to firms manufacturing or importing dietary supplements that contain specific bovine tissues. FDA. Available at: www.cfsan.fda.gov/~dms/dspltr05.html.
  • Swelling Additional detail

    “Parenterally, transfer factor may cause tenderness, pain, and swelling at the injection site.”

    Transfer Factor · Natural Medicines adverse-effect record, reported in pain.

    4 sources cited
    1. 3062. Miller LL, Spitler LE, Allen RE, Minor DR. A randomized, double-blind, placebo-controlled trial of transfer factor as adjuvant therapy for malignant melanoma. Cancer 1988;61:1543-9. PubMed
    2. 7562. Lloyd AR, Hickie I, Brockman A, et al. Immunologic and psychologic therapy for patients with chronic fatigue syndrome: a double-blind, placebo-controlled trial. Am J Med 1993;94:197-203. PubMed
    3. 7799. Fog T, Pedersen L, Raun NE, et al. Long-term transfer-factor treatment for multiple sclerosis. Lancet 1978;1:851-3. PubMed
    4. 78809. Fernandez, O., Diaz, N., Morales, E., Toledo, J., Hernandez, E., Rojas, S., Madriz, X., and Lopez, Saura P. Effect of transfer factor on myelosuppression and related morbidity induced by chemotherapy in acute leukaemias. Br.J.Haematol. 1993;84(3):423-427 PubMed
  • Tiredness Additional detail

    “Parenterally, fatigue has been reported for up to 4 hours in a patient using transfer factor.”

    Transfer Factor · Natural Medicines adverse-effect record, reported in fatigue.

    1 source cited
    1. 78789. Thestrup-Pedersen, K., Grunnet, E., and Zachariae, H. Transfer factor therapy in mycosis fungoides: a double-blind study. Acta Derm.Venereol. 1982;62(1):47-53. DOI
  • Nausea Additional detail

    “Parenterally, nausea has been reported in a patient following treatment with transfer factor”

    Transfer Factor · Natural Medicines adverse-effect record, reported in nausea and vomiting.

    1 source cited
    1. 78809. Fernandez, O., Diaz, N., Morales, E., Toledo, J., Hernandez, E., Rojas, S., Madriz, X., and Lopez, Saura P. Effect of transfer factor on myelosuppression and related morbidity induced by chemotherapy in acute leukaemias. Br.J.Haematol. 1993;84(3):423-427 PubMed

Everything above comes from the Natural Medicines adverse-effect record for Transfer Factor — expand a row for the licensed statement it rests on. We haven’t matched Interferon Alfa-2b to its FDA label in our system yet, so we can’t compare its own side-effect list here — the leaflet that comes with your prescription is the authoritative list for Interferon Alfa-2b.

Overlapping uses

What Interferon Alfa-2b Is Prescribed For, and What Transfer Factor Has Been Studied For

These two come up together because they touch the same health topic — not because they do the same job. Interferon Alfa-2b is a prescription medicine with approved uses on its FDA label. Transfer Factor is a supplement: what follows is what researchers have looked at it for, and how strong that evidence is.

Transfer Factor has been studied for:

  • Melanoma studied, not established Transfer Factor has been studied for this. Natural Medicines rates the evidence: Possibly Ineffective Read what the research shows

    Transfer Factor for melanoma

    Administering human-derived transfer factor intramuscularly or subcutaneously, as adjuvant therapy, does not seem to affect disease progression or prolong survival when used for up to 2 years following surgery for Stage I and Stage II melanoma.

    3 sources cited
    1. 3062. Miller LL, Spitler LE, Allen RE, Minor DR. A randomized, double-blind, placebo-controlled trial of transfer factor as adjuvant therapy for malignant melanoma. Cancer 1988;61:1543-9. PubMed
    2. 3063. Bukowski RM, Deodhar S, Hewlett JS, Greenstreet R. Randomized controlled trial of transfer factor in Stage II malignant melanoma. Cancer 1983;51:269-72. PubMed
    3. 78691. Miller, L. L., Spitler, L. E., Allen, R. E., and Minor, D. R. A randomized, double-blind, placebo-controlled trial of transfer factor as adjuvant therapy for malignant melanoma. Cancer 4-15-1988;61(8):1543-1549. PubMed
  • Hepatitis B studied, not established Transfer Factor has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Transfer Factor for hepatitis b

    Some preliminary clinical evidence suggests that transfer factor derived from patients with acute hepatitis B, given intramuscularly, might be useful for treating chronic active hepatitis B infection. Other preliminary clinical research shows that transfer factor derived from patients with acute hepatitis B, given subcutaneously, does not improve biochemical parameters in patients with chronic active hepatitis B infe…

    2 sources cited
    1. 7797. Roda E, Viza D, Pizza G, et al. Transfer factor for the treatment of HBsAg-positive chronic active hepatitis. Proc Soc Exp Biol Med 1985;178:468-75. PubMed
    2. 78775. Ellis-Pegler, R., Sutherland, D. C., Douglas, R., Woodfield, D. G., and Wilson, J. D. Transfer factor and hepatitis B: a double blind study. Clin.Exp.Immunol. 1979;36(2):221-226.
  • Leukemia studied, not established Transfer Factor has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Transfer Factor for leukemia

    Preliminary clinical research shows that administering transfer factor subcutaneously reduces time to neutrophil and leukocyte count recovery compared to control in patients with acute leukemia.

    1 source cited
    1. 78809. Fernandez, O., Diaz, N., Morales, E., Toledo, J., Hernandez, E., Rojas, S., Madriz, X., and Lopez, Saura P. Effect of transfer factor on myelosuppression and related morbidity induced by chemotherapy in acute leukaemias. Br.J.Haematol. 1993;84(3):423-427 PubMed

Effectiveness ratings and the research summaries above are the verbatim record from the Natural Medicines database, which grades evidence from “Effective” down to “Insufficient Reliable Evidence To Rate”. A rating below the top of that scale means researchers have looked at it — not that it works, and never that it can stand in for a prescribed medicine. Do not stop or replace Interferon Alfa-2b on your own; if you are taking Transfer Factor for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

Everything else you take

See Every Supplement That Interacts With Interferon Alfa-2b

This page covers Transfer Factor only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Interferon Alfa-2b page lists 57 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Beer (major), Siberian Cocklebur (major), Wine (major), Alfalfa (moderate) and Angelica Archangelica (moderate).

By severity: 3 major · 53 moderate · 1 minor.

From our pharmacist’s overview on the Interferon Alfa-2b page

“People taking interferon alfa-2b (Intron A, Rebetron) are usually treating hepatitis or a cancer, so the liver may already be under strain, and that is exactly where most of this list points. Of the 57 supplements on file, 38 can add to liver stress, and all three major-rated interactions sit in that group: Siberian cocklebur, which ha…”

Reviewed by 2 · Jul 18, 2026

Open the Interferon Alfa-2b interaction page

How much people look this up

Where Transfer Factor and Interferon Alfa-2b Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Transfer Factor
Steady interest

#812 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Interferon Alfa-2b
Steady interest

#2,087 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Transfer Factor reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Transfer Factor and Interferon Alfa-2b records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Transfer Factor

What is Transfer Factor?

  • Immune support
  • Preventing colds and infections
  • Allergies
  • General wellness
  • Chronic viral conditions

Transfer factors are small immune molecules taken from cow colostrum or egg yolk and sold as supplements meant to boost or 'train' the immune system. Solid human evidence for the supplement products is limited, and quality varies widely between brands. Talk with your pharmacist or doctor before using one, especially if you have an immune condition.

Small immune molecules (peptides) extracted from sources such as cow colostrum or hen egg yolk · Capsules, tablets, powders

An interaction check asks whether these two react with each other — it does not ask whether Transfer Factor is a good idea for someone in your situation. Here is what our Transfer Factor record says about it on its own.

Transfer Factor: dosing

There is no official or standardized dose for transfer factor supplements. Because products differ in how they are made and how concentrated they are, the right amount is hard to define.The safest approach is to follow the directions on the product label and not exceed the recommended amount. They can help you decide if a product is appropriate and reasonable.

From our Transfer Factor monograph — the full record covers uses, side effects and every documented interaction.

Read the full Transfer Factor monograph & all interactions
Medication

About Interferon Alfa-2b Injection

What Is Interferon Alfa-2b Injection Used For?

Brand names: Rebetron, Intron A, Viraferon

  • Interferon alfa-2b injection is used to treat a number of conditions.

  • Interferon alfa-2b injection is used

    • alone or in combination with ribavirin (Copegus, Rebetol, Ribasphere) to treat chronic (long-term) hepatitis C infection (swelling of the liver caused by a virus) in people who show signs of liver damage,

    • to treat chronic hepatitis B infection (swelling of the liver caused by a virus) in people who show signs of liver damage,

    • to treat hairy cell leukemia (a white blood cell cancer),

    • to treat genital warts,

    • to treat Kaposi's sarcoma (a type of cancer that causes abnormal tissue to grow on different parts of the body) related to acquired immunodeficiency syndrome (AIDS),

    • to treat malignant melanoma (a cancer that begins in certain skin cells) in certain people who have had surgery to remove the cancer,

    • along with another medication to treat follicular non-Hodgkin's lymphoma (NHL; a slow-growing blood cancer).

  • Interferon alfa-2b is in a class of medications called immunomodulators. Interferon alfa-2b works to treat hepatitis C virus (HCV) and hepatitis B virus (HBV) by decreasing the amount virus in the body. Interferon alfa-2b may not cure hepatitis B or hepatitis C or prevent you from developing complications from these infections such as cirrhosis (scarring) of the liver, liver failure, or liver cancer. It also may not prevent the spread of hepatitis B or C to other people. It is not known exactly how interferon alfa-2b works to treat cancer or genital warts.

See full Interferon Alfa-2b Injection drug information
Keep checking

Other Drugs & Transfer Factor

Browse every other medication we’ve checked against Transfer Factor — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
0Moderate
0Minor
2,829No known interaction
No interaction 2,829 drugs checked — show the list
Evidence & sources

Transfer Factor References

The 49 references that drive our Transfer Factor monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Jones JF, Minnich LL, Jeter WS, et al. Treatment of childhood combined Epstein-Barr virus/cytomegalovirus infection with oral bovine transfer factor. Lancet 1981;2:122-4. PubMed
  2. Steele RW, Myers MG, Vincent MM. Transfer factor for the prevention of varicella-zoster infection in childhood leukemia. N Engl J Med 1980;303:355-9. PubMed
  3. Louie E, Borkowsky W, Klesius PH, et al. Treatment of cryptosporidiosis with oral bovine transfer factor. Clin Immunol Immunopathol 1987;44:329-34. PubMed
  4. McMeeking A, Borkowsky W, Klesius PH, et al. A controlled trial of bovine dialyzable leukocyte extract for cryptosporidiosis in patients with AIDS. J Infect Dis 1990;161:108-12. PubMed
  5. Fudenberg HH. Transfer factor: past, present and future. Annu Rev Pharmacol Toxicol 1989;29:475-516. PubMed
  6. Lewis CJ. Letter to reiterate certain public health and safety concerns to firms manufacturing or importing dietary supplements that contain specific bovine tissues. FDA. Available at: www.cfsan.fda.gov/~dms/dspltr05.html.
  7. Miller LL, Spitler LE, Allen RE, Minor DR. A randomized, double-blind, placebo-controlled trial of transfer factor as adjuvant therapy for malignant melanoma. Cancer 1988;61:1543-9. PubMed
  8. Bukowski RM, Deodhar S, Hewlett JS, Greenstreet R. Randomized controlled trial of transfer factor in Stage II malignant melanoma. Cancer 1983;51:269-72. PubMed
  9. Bowden RA, Siegel MS, Steele RW, et al. Immunologic and clinical responses to varicella-zoster virus-specific transfer factor following marrow ransplantation. J Infect Dis 1985;152:1324-7.
  10. Sharma MK, Anaraki F, Ala F. Preliminary results of transfer factor therapy of persistant cutaneous leishmania infection. Clin Immunol Immunopathol 1979;12:183-90. PubMed
  11. Whyte RI, Schork MA, Sloan H, et al. Adjuvant treatment using transfer factor for bronchogenic carcinoma: long-term follow-up. Ann Thorac Surg 1992;53:391-6. PubMed
  12. Lloyd AR, Hickie I, Brockman A, et al. Immunologic and psychologic therapy for patients with chronic fatigue syndrome: a double-blind, placebo-controlled trial. Am J Med 1993;94:197-203. PubMed
  13. Spitler LE. Transfer factor therapy in the Wiskott-Aldrich syndrome. Results of long-term follow-up in 32 patients. Am J Med 1979;67:59-66.
  14. Roda E, Viza D, Pizza G, et al. Transfer factor for the treatment of HBsAg-positive chronic active hepatitis. Proc Soc Exp Biol Med 1985;178:468-75. PubMed
  15. Basten A, McLeod JG, Pollard JD, et al. Transfer factor in treatment of multiple sclerosis. Lancet 1980;2:931-4. PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Transfer Factor and Interferon Alfa-2b Together: Common Questions

Is it safe to take Transfer Factor with Interferon Alfa-2b?
We do not list a known interaction between Transfer Factor and Interferon Alfa-2b. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
Are Transfer Factor and Interferon Alfa-2b used for the same thing?
They overlap in purpose, which usually means the real question is whether you need both rather than whether they are safe together. This page lists the shared uses and how strong the evidence is for Transfer Factor in each. That is a conversation for your prescriber, especially if Interferon Alfa-2b is being adjusted to a target.
Does Interferon Alfa-2b interact with any supplements?
Yes. Interferon Alfa-2b has documented interactions with 57 supplements in our database — Transfer Factor is not one of them. The Interferon Alfa-2b interaction page linked on this page lists every one, ranked by severity.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Interferon Alfa-2b and Transfer Factor?

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.