Drug & supplement interaction

Gelatin + Acyclovir

Acyclovir brand names: Zovirax, Zovirax Injection, Sitavig, Avaclyr.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Gelatin and Acyclovir 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. Additionally, although there is no interaction, the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

Gelatin and Acyclovir

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 Acyclovir and Gelatin 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 Gelatin at all — not against Acyclovir, 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.

Gelatin safety at a glance

Gelatin overall Generally safe Gelatin is widely consumed as a food and is generally considered safe for most people.
Pregnancy Likely Safe When used orally in the amounts commonly found in foods. Read the full pregnancy detail
Breastfeeding Likely Safe When used orally in the amounts commonly found in foods. There is insufficient reliable information available about the safety of using larger amounts of gelati... Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Acyclovir and Gelatin? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

No Interaction Found — But Data Suggests Gelatin and Acyclovir May Share a Side Effect

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do. One of them is worth acting on rather than waiting out — marked below.

  • Kidney problems Worth acting on Additional detail

    Gelatin

    “Gelatin can cause allergic reactions. Gelatin in foods can cause initial sensitization. Gelatin-containing medicines including oral medications, suppositories, vaccines, and injectable products can cause IgE-mediated allergic reactions, including urticaria, angioedema, wheezing, hypotension, and anaphylaxis.”

    Gelatin · Natural Medicines adverse-effect record, reported in hypotension.

    6 sources cited
    1. 7703. Schwick HG, Heide K. Immunochemistry and immunology of collagen and gelatin. Bibl Haematol 1969;33:111-25. PubMed
    2. 7708. Kelso JM. The gelatin story. J Allergy Clin Immunol 1999;103:200-2.
    3. 7709. Nakayama T, Aizawa C, Kuno-Sakai H. A clinical analysis of gelatin allergy and determination of its causal relationship to the previous administration of gelatin-containing acellular pertussis vaccine combined with diphtheria and tetanus toxoids. J Allerg PubMed
    4. 7710. Sakaguchi M, Inouye S. Anaphylaxis to gelatin-containing rectal suppositories. J Allergy Clin Immunol 2001;108:1033-4. PubMed
    5. 97633. Ventura Spagnolo E, Calapai G, Minciullo PL, Mannucci C, Asmundo A, Gangemi S. Lethal anaphylactic reaction to intravenous gelatin in the course of surgery. Am J Ther. 2016;23(6):e1344-e1346. PubMed
    6. 111345. Coury JR, Skaggs KF, Marciano GF, et al. Intraoperative Anaphylaxis to the Bovine Flowable Gelatin Matrix: A Report of 2 Cases. JBJS Case Connect 2022;12(1). PubMed

    Acyclovir

    Listed in the ADVERSE REACTIONS section of the FDA label for Acyclovir. Read the label on DailyMed ›

Reported for Gelatin but not commonly for Acyclovir: an allergic reaction, a fast or pounding heartbeat, a slow heartbeat and low blood pressure.

Effects for Acyclovir come from the ADVERSE REACTIONS section of its FDA label; effects for Gelatin come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 114,761 voluntary FDA FAERS reports for Acyclovir that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Special populations

Gelatin in Pregnancy & Breastfeeding

Pregnancy Likely Safe

When used orally in the amounts commonly found in foods.

Pregnancy Possibly Safe

When a specific type of gelatin from donkey hide, called colla corii asini, is used orally in doses of 10 grams daily for 6 weeks. Higher doses of 15 grams daily have been associated with an increased risk of inflammatory adverse effects, including sore throat, swollen gums, local eczema, and ulcers in the oral cavity. There is insufficient reliable information available about the safety of other types of gelatin when used during pregnancy in medicinal amounts.

Lactation Likely Safe

When used orally in the amounts commonly found in foods. There is insufficient reliable information available about the safety of using larger amounts of gelatin during lactation; avoid using.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

From our Q&A

Questions About Gelatin or Acyclovir

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Gelatin or Acyclovir, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Acyclovir

This page covers Gelatin only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Acyclovir page lists 37 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Asarabacca (major), Siberian Cocklebur (major), African Wild Potato (moderate) and Aristolochia (moderate).

By severity: 3 major · 23 moderate · 11 minor.

From our pharmacist’s overview on the Acyclovir page

“Kidney strain is the risk to understand first. Acyclovir (Zovirax) can stress the kidneys on its own, and a few ingredients here, Siberian cocklebur especially, are toxic to kidney tissue, so pairing them could compound the harm.”

Reviewed by 2 · Jul 18, 2026

Open the Acyclovir interaction page

One more smart check

Taking Gelatin as Part of a Dietary Supplement Product? Check It for Interactions

We hold 269 real supplement products containing Gelatin, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Gelatin. Even though Gelatin itself has no known interaction with Acyclovir, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Gelatin and Acyclovir 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 Gelatin
Top half

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

29 days ago today
Medication Acyclovir
Top 5%

#59 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 Gelatin reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Gelatin and Acyclovir records this page draws on were last updated July 11, 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 Gelatin

What is Gelatin?

  • Joint and bone health
  • Skin, hair, and nail support
  • Source of dietary protein
  • Digestive comfort
  • Capsule shells for medicines and supplements

Gelatin is a protein made from animal collagen, used as a food, a capsule ingredient, and a supplement for joint, skin, and bone health. For most health uses, the evidence is limited or mixed, though it is generally safe as a food. If you have allergies, dietary restrictions, or a health condition, check with your pharmacist or doctor first.

Collagen derived from animal skin, bones, and connective tissue (usually pork or beef) · Powder, capsules, gummies, food products (Jell-O type desserts), and collagen/gelatin drinks

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

Gelatin: dosing

There is no official, standardized dose of gelatin for any health condition. The amount used in studies varies widely, and it is not clear what dose, if any, provides a health benefit.If you choose to use a gelatin supplement, follow the directions on the product label and do not exceed the recommended amount.

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

Read the full Gelatin monograph & all interactions
Medication

About Acyclovir

What Is Acyclovir Used For?

Brand names: Zovirax, Zovirax Injection, Sitavig, Avaclyr

Acyclovir treats infections caused by herpes viruses. Depending on the form, it is used for cold sores (herpes labialis), genital herpes (initial episodes and recurrent flare-ups), shingles (herpes zoster), and chickenpox (varicella). It can also be used long-term to suppress recurrent genital herpes outbreaks.

Some forms are approved for more serious situations: acyclovir injection is used in hospital settings for herpes simplex encephalitis (herpes infection of the brain), neonatal herpes (in newborns), and herpes or shingles infections in immunocompromised patients. Avaclyr ophthalmic ointment is specifically indicated for acute herpetic keratitis (a herpes ulcer on the cornea of the eye). Sitavig buccal tablet and Zovirax cream are specifically indicated for recurrent cold sores in immunocompetent adults.

Most-Reported Side Effects for Acyclovir

From FAERS, the FDA’s public side-effect reporting system (114,761 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Fatigue 8,029 reports
Diarrhea 7,348 reports
Pneumonia 5,700 reports
Nausea 5,643 reports
Fever 4,989 reports
See full Acyclovir drug information
Keep checking

Other Drugs & Gelatin

Browse every other medication we’ve checked against Gelatin — 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

Gelatin References

The 11 references that drive our Gelatin 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. 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.
  2. Schwick HG, Heide K. Immunochemistry and immunology of collagen and gelatin. Bibl Haematol 1969;33:111-25. PubMed
  3. Moskowitz RW. Role of collagen hydrolysate in bone and joint disease.Semin Arthritis Rheum 2000;30:87-99. PubMed
  4. Kelso JM. The gelatin story. J Allergy Clin Immunol 1999;103:200-2.
  5. Nakayama T, Aizawa C, Kuno-Sakai H. A clinical analysis of gelatin allergy and determination of its causal relationship to the previous administration of gelatin-containing acellular pertussis vaccine combined with diphtheria and tetanus toxoids. J Allerg PubMed
  6. Sakaguchi M, Inouye S. Anaphylaxis to gelatin-containing rectal suppositories. J Allergy Clin Immunol 2001;108:1033-4. PubMed
  7. PDR Electronic Library. Montvale, NJ: Medical Economics Company, Inc., 2001.
  8. de la Fuente Tornero E, Vega Castro A, de Sierra Hernández PÁ, et al. Kounis syndrome during anesthesia: Presentation of indolent systemic mastocytosis: A case report. A Case Rep. 2017;8(9):226-228. PubMed
  9. Ventura Spagnolo E, Calapai G, Minciullo PL, Mannucci C, Asmundo A, Gangemi S. Lethal anaphylactic reaction to intravenous gelatin in the course of surgery. Am J Ther. 2016;23(6):e1344-e1346. PubMed
  10. Li Y, He H, Yang L, Li X, Li D, Luo S. Therapeutic effect of Colla corii asini on improving anemia and hemoglobin compositions in pregnant women with thalassemia. Int J Hematol. 2016;104(5):559-565. PubMed
  11. Coury JR, Skaggs KF, Marciano GF, et al. Intraoperative Anaphylaxis to the Bovine Flowable Gelatin Matrix: A Report of 2 Cases. JBJS Case Connect 2022;12(1). 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 Gelatin and Acyclovir Together: Common Questions

Is it safe to take Gelatin with Acyclovir?
We do not list a known interaction between Gelatin and Acyclovir. 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.
Do Gelatin and Acyclovir have any of the same side effects?
Yes — our sources link each of them separately to one of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
Does Acyclovir interact with any supplements?
Yes. Acyclovir has documented interactions with 37 supplements in our database — Gelatin is not one of them. The Acyclovir 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 Acyclovir and Gelatin?

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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.