Drug & supplement interaction

Sangre De Grado + Valacyclovir

Valacyclovir brand name: Valtrex.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Sangre De Grado and Valacyclovir 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

Sangre De Grado and Valacyclovir

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 Valacyclovir and Sangre De Grado 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 Sangre De Grado at all — not against Valacyclovir, 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.

Sangre De Grado safety at a glance

Sangre De Grado overall Use caution It has a long history of traditional use but limited safety data for supplements, so use cautiously.
Pregnancy Avoid There is not enough safety information, so avoid use during pregnancy.
Breastfeeding Avoid Safety while breastfeeding is unknown, so it is best to avoid it.

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

Still wondering about combining Valacyclovir and Sangre De Grado? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

No Interaction Found — But Data Suggests Sangre De Grado and Valacyclovir May Share Several of the Same Side Effects

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.

  • Stomach pain / Diarrhea Additional detail

    Sangre De Grado

    “Orally, gastrointestinal adverse effects have been reported in some patients taking the sangre de grado constituent crofelemer (SP-303). In a clinical trial of patients with diarrhea-predominant irritable bowel syndrome, constipation, flatulence, or abdominal pain was reported in 5% to 7% of patients taking crofelemer compared to only 2% to 3% of patients taking placebo.”

    Sangre De Grado · Natural Medicines adverse-effect record, reported in constipation.

    2 sources cited
    1. 94708. MacArthur RD, Hawkins T, Brown SJ, et al. Efficacy and safety of crofelemer for noninfectious diarrhea in HIV-seropositive individuals (ADVENT trial): a randomized, double-blind, placebo-controlled, two-stage study. HIV Clin Trials 2013;14(6):261-73. PubMed
    2. 94709. Mangel AW, Chaturvedi P. Evaluation of crofelemer in the treatment of diarrhea-predominant irritable bowel syndrome patients. Digestion 2008;78(4):180-6. PubMed

    Valacyclovir

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

  • Headache Additional detail

    Sangre De Grado

    “Orally, crofelemer (SP-303), a purified constituent of sangre de grado, seems to be well tolerated. No serious adverse effects have been reported in clinical studies. Mild gastrointestinal adverse effects, bronchitis, and headache have been reported in clinical research with oral crofelemer (SP-303).

    Topically, the sangre de grado constituent crofelemer can cause local pain and burning.”

    Sangre De Grado · Natural Medicines adverse-effect record, reported in acute bronchitis.

    6 sources cited
    1. 2784. Holodniy M, Koch J, Mistal M, et al. A double blind, randomized, placebo-controlled phase II study to assess the safety and efficacy of orally administered SP-303 for the symptomatic treatment of diarrhea in patients with AIDS. Am J Gastroenterol 1999;9 PubMed
    2. 2806. Dicesare D, Dupont HL, Mathewson JJ, et al. A double-blind randomized, placebo-controlled study of SP-303 (Provir) in the symptomatic treatment of acute diarrhea among travelers to Mexico and Jamaica. Infectious Diseases Society of America Annual Meetin
    3. 73090. DiCesare, D., DuPont, H. L., Mathewson, J. J., Ashley, D., Martinez-Sandoval, F., Pennington, J. E., and Porter, S. B. A double blind, randomized, placebo-controlled study of SP-303 (Provir) in the symptomatic treatment of acute diarrhea among travelers
    4. 94708. MacArthur RD, Hawkins T, Brown SJ, et al. Efficacy and safety of crofelemer for noninfectious diarrhea in HIV-seropositive individuals (ADVENT trial): a randomized, double-blind, placebo-controlled, two-stage study. HIV Clin Trials 2013;14(6):261-73. PubMed
    5. 94709. Mangel AW, Chaturvedi P. Evaluation of crofelemer in the treatment of diarrhea-predominant irritable bowel syndrome patients. Digestion 2008;78(4):180-6. PubMed
    6. 103246. Nee J, Salley K, Ludwig AG, et al. Randomized clinical trial: crofelemer treatment in women with diarrhea-predominant irritable bowel syndrome. Clin Transl Gastroenterol. 2019;10(12):e00110. PubMed

    “Orally, headache has been reported in some patients taking the sangre de grado constituent crofelemer (SP-303).”

    Sangre De Grado · Natural Medicines adverse-effect record, reported in cluster headache.

    1 source cited
    1. 103246. Nee J, Salley K, Ludwig AG, et al. Randomized clinical trial: crofelemer treatment in women with diarrhea-predominant irritable bowel syndrome. Clin Transl Gastroenterol. 2019;10(12):e00110. PubMed

    Valacyclovir

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

Reported for Sangre De Grado but not commonly for Valacyclovir: constipation and bloating or gas.

Effects for Valacyclovir come from the ADVERSE REACTIONS section of its FDA label; effects for Sangre De Grado come from the Natural Medicines adverse-effect record, quoted above. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Overlapping uses

What Valacyclovir Is Prescribed For, and What Sangre De Grado Has Been Studied For

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

Valacyclovir is prescribed for: Valacyclovir tablets are used in adults to treat cold sores (herpes labialis), genital herpes (initial and recurrent episodes), and shingles (herpes zoster). They can also be taken daily as suppressive therapy to reduce how often genital herpes outbreaks occur, and to lower the risk of passing genital herpes to a partner. In children and adolescents, valacyclovir tablets are used to treat cold sores in those aged 12 and older, and chickenpox in those aged 2 to under 18. Valacyclovir has not been established as safe and effective for most uses in immunocompromised patients, with the exception of suppressive therapy for genital herpes in HIV-infected adults.

Sangre De Grado has been studied for:

  • Genital herpes Natural Medicines rates the evidence for Sangre De Grado: Possibly Effective Read what the research shows

    Sangre De Grado for genital herpes

    Some clinical research shows that topical application of a specific sangre de grado ointment (Virend, Shaman Pharmaceuticals), containing purified crofelemer (SP-303) 15%, three times daily for 21 days seems to be effective for treating genital and anal herpes simplex lesions in people with AIDS.

    2 sources cited
    1. 2788. Orozco-Topete R, Sierra-Madero J, Cano-Dominguez C, et al. Safety and efficacy of Virend for topical treatment of genital and anal herpes simplex lesions in patients with AIDS. Antiviral Res 1997;35:91-103. PubMed
    2. 2787. Safrin S, McKinley G, McKeough M, et al. Treatment of acyclovir-unresponsive cutaneous herpes simplex virus infection with topically applied SP-303. Antiviral Res 1994;25:185-92. 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 Valacyclovir on your own; if you are taking Sangre De Grado for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

From our Q&A

Questions About Sangre De Grado or Valacyclovir

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Sangre De Grado or Valacyclovir, 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 Valacyclovir

This page covers Sangre De Grado only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Valacyclovir page lists 27 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), African Wild Potato (moderate), Banderol (moderate), Biofeedback (moderate) and Caffeic Acid (moderate).

By severity: 1 major · 17 moderate · 9 minor.

From our pharmacist’s overview on the Valacyclovir page

“Valacyclovir (Valtrex) works against herpes outbreaks only if enough of it gets absorbed into your blood, and most of this list threatens exactly that. Of the 27 supplements on file, 17 can change how well oral medicines like this one are absorbed, and the single major-rated entry, activated charcoal, binds drugs in the gut outright.”

Reviewed by 2 · Jul 18, 2026

Open the Valacyclovir interaction page

One more smart check

Taking Sangre De Grado as Part of a Dietary Supplement Product? Check It for Interactions

We hold 27 real supplement products containing Sangre De Grado, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Sangre De Grado. Even though Sangre De Grado itself has no known interaction with Valacyclovir, 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 Sangre De Grado and Valacyclovir 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 Sangre De Grado
Steady interest

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

29 days ago today
Medication Valacyclovir
Top 5%

#31 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 Sangre De Grado reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Sangre De Grado and Valacyclovir 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 Sangre De Grado

What is Sangre De Grado?

  • Diarrhea
  • Wound healing and skin sores
  • Digestive and stomach complaints
  • Insect bites and minor skin irritation
  • Sore throat and mouth ulcers

Sangre de Grado is a red tree sap from the Amazon rainforest used traditionally for diarrhea, wounds, and skin problems. Some of its compounds have been studied scientifically, and one purified ingredient (crofelemer) is used in a prescription anti-diarrhea drug, but the raw supplement itself has limited human research. Talk with a pharmacist or doctor before using it, especially if you are pregnant, breastfeeding, or have a health condition.

Croton lechleri · Euphorbiaceae · Red sap (latex) from the bark of the tree · Liquid sap, tincture, topical gel or cream, capsules, and a purified extract (crofelemer) used in some medicines

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

Sangre De Grado: dosing

There is no official, standardized dose for Sangre de Grado supplements. The right amount can depend on the form (liquid sap, tincture, gel, or capsule) and the concentration of the specific product.If you choose to use it, follow the directions on the product label and do not exceed the recommended amount.

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

Read the full Sangre De Grado monograph & all interactions
Medication

About Valacyclovir

What Is Valacyclovir Used For?

Brand name: Valtrex

Valacyclovir tablets are used in adults to treat cold sores (herpes labialis), genital herpes (initial and recurrent episodes), and shingles (herpes zoster). They can also be taken daily as suppressive therapy to reduce how often genital herpes outbreaks occur, and to lower the risk of passing genital herpes to a partner.

In children and adolescents, valacyclovir tablets are used to treat cold sores in those aged 12 and older, and chickenpox in those aged 2 to under 18. Valacyclovir has not been established as safe and effective for most uses in immunocompromised patients, with the exception of suppressive therapy for genital herpes in HIV-infected adults.

Most-Reported Side Effects for Valacyclovir

From FAERS, the FDA’s public side-effect reporting system (70,056 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Fatigue 4,317 reports
Nausea 3,985 reports
Diarrhea 3,648 reports
Headache 2,964 reports
Fever 2,753 reports
See full Valacyclovir drug information
Keep checking

Other Drugs & Sangre De Grado

Browse every other medication we’ve checked against Sangre De Grado — 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

Sangre De Grado References

The 9 references that drive our Sangre De Grado 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. Holodniy M, Koch J, Mistal M, et al. A double blind, randomized, placebo-controlled phase II study to assess the safety and efficacy of orally administered SP-303 for the symptomatic treatment of diarrhea in patients with AIDS. Am J Gastroenterol 1999;9 PubMed
  2. Safrin S, McKinley G, McKeough M, et al. Treatment of acyclovir-unresponsive cutaneous herpes simplex virus infection with topically applied SP-303. Antiviral Res 1994;25:185-92. PubMed
  3. Orozco-Topete R, Sierra-Madero J, Cano-Dominguez C, et al. Safety and efficacy of Virend for topical treatment of genital and anal herpes simplex lesions in patients with AIDS. Antiviral Res 1997;35:91-103. PubMed
  4. Dicesare D, Dupont HL, Mathewson JJ, et al. A double-blind randomized, placebo-controlled study of SP-303 (Provir) in the symptomatic treatment of acute diarrhea among travelers to Mexico and Jamaica. Infectious Diseases Society of America Annual Meetin
  5. Miller, M. J., Vergnolle, N., McKnight, W., Musah, R. A., Davison, C. A., Trentacosti, A. M., Thompson, J. H., Sandoval, M., and Wallace, J. L. Inhibition of neurogenic inflammation by the Amazonian herbal medicine sangre de grado. J.Invest Dermatol. 200 PubMed
  6. DiCesare, D., DuPont, H. L., Mathewson, J. J., Ashley, D., Martinez-Sandoval, F., Pennington, J. E., and Porter, S. B. A double blind, randomized, placebo-controlled study of SP-303 (Provir) in the symptomatic treatment of acute diarrhea among travelers
  7. MacArthur RD, Hawkins T, Brown SJ, et al. Efficacy and safety of crofelemer for noninfectious diarrhea in HIV-seropositive individuals (ADVENT trial): a randomized, double-blind, placebo-controlled, two-stage study. HIV Clin Trials 2013;14(6):261-73. PubMed
  8. Mangel AW, Chaturvedi P. Evaluation of crofelemer in the treatment of diarrhea-predominant irritable bowel syndrome patients. Digestion 2008;78(4):180-6. PubMed
  9. Nee J, Salley K, Ludwig AG, et al. Randomized clinical trial: crofelemer treatment in women with diarrhea-predominant irritable bowel syndrome. Clin Transl Gastroenterol. 2019;10(12):e00110. 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 Sangre De Grado and Valacyclovir Together: Common Questions

Is it safe to take Sangre De Grado with Valacyclovir?
We do not list a known interaction between Sangre De Grado and Valacyclovir. 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 Sangre De Grado and Valacyclovir have any of the same side effects?
Yes — our sources link each of them separately to 3 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.
Are Sangre De Grado and Valacyclovir 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 Sangre De Grado in each. That is a conversation for your prescriber, especially if Valacyclovir is being adjusted to a target.
Does Valacyclovir interact with any supplements?
Yes. Valacyclovir has documented interactions with 27 supplements in our database — Sangre De Grado is not one of them. The Valacyclovir 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 Valacyclovir and Sangre De Grado?

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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.