Drug & supplement interaction

Fever Bark + Gabapentin

Gabapentin brand names: Neurontin, Gralise.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Fever Bark and Gabapentin 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

Fever Bark and Gabapentin

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 Gabapentin and Fever Bark 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.

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.

Fever Bark safety at a glance

Fever Bark overall Use caution The bark contains strong alkaloids and is not recommended without professional supervision.
Pregnancy Avoid Not enough safety data and potent alkaloids make it unsafe to use during pregnancy.
Breastfeeding Avoid No reliable safety information exists, so avoid use while breastfeeding.

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

Still wondering about combining Gabapentin and Fever Bark? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Gabapentin

Interactions in our licensed database are recorded against drug classes, not just single drug names. Gabapentin is filed under 4 classifications — including anticonvulsants, cns depressants, oral drugs. Fever Bark has documented interactions with 9 drug classes — the most serious being anesthesia (major), monoamine oxidase inhibitors (maois) (major) and antihypertensive drugs (moderate) — and none of Gabapentin’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Fever Bark Does Interact With Other Medications

Fever Bark has 40 major, 674 moderate, 87 minor known drug interactions in our database — Gabapentin isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Fever Bark

Covers the 2,830 medications we’ve checked against Fever Bark. Pick one to open its full report.

What to actually watch for

No Interaction Found — But Data Suggests Fever Bark and Gabapentin 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. 3 of them are worth acting on rather than waiting out — marked below.

  • Seizures Worth acting on Additional detail

    Fever Bark

    “The yohimbine constituent of fever bark, when taken alone in high doses, causes general central nervous system and autonomic excitation, tremulousness, head twitching, seizure threshold changes, dizziness, vertigo, and headache. It is not known if this occurs with fever bark.”

    Fever Bark · Natural Medicines adverse-effect record, reported in cluster headache.

    6 sources cited
    1. 3312. Teloken C, Rhoden EL, Sogari P, et al. Therapeutic effects of high dose yohimbine hydrochloride on organic erectile dysfunction. J Urol 1998;159:122-4. PubMed
    2. 3971. Hollander E, McCarley A. Yohimbine treatment of sexual side effects induced by serotonin reuptake blockers. J Clin Psychiatry 1992;53:207-9.
    3. 86774. Cameron, O. G., Zubieta, J. K., Grunhaus, L., and Minoshima, S. Effects of yohimbine on cerebral blood flow, symptoms, and physiological functions in humans. Psychosom.Med 2000;62(4):549-559. PubMed
    4. 86779. Bowes, M. P., Peters, R. H., Kernan, W. J., Jr., and Hopper, D. L. Effects of yohimbine and idazoxan on motor behaviors in male rats. Pharmacol.Biochem.Behav. 1992;41(4):707-713.
    5. 86786. Adeniyi, A. A., Brindley, G. S., Pryor, J. P., and Ralph, D. J. Yohimbine in the treatment of orgasmic dysfunction. Asian J Androl 2007;9(3):403-407. PubMed
    6. 86804. Myers, A. and Barrueto, F., Jr. Refractory priapism associated with ingestion of yohimbe extract. J Med Toxicol. 2009;5(4):223-225.

    Gabapentin

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

  • Low mood Worth acting on Additional detail

    Fever Bark

    “The yohimbine constituent of fever bark, when taken alone, causes malaise, fatigue, irritability insomnia, restlessness, agitation, and anxiety. The reserpine constituent of fever bark, when taken alone, causes depression (17). It is not known if these effects occur with fever bark.”

    Fever Bark · Natural Medicines adverse-effect record, reported in anxiety.

    6 sources cited
    1. 3312. Teloken C, Rhoden EL, Sogari P, et al. Therapeutic effects of high dose yohimbine hydrochloride on organic erectile dysfunction. J Urol 1998;159:122-4. PubMed
    2. 3970. Jacobsen FM. Fluoxetine-induced sexual dysfunction and an open trial of yohimbine. J Clin Psychiatry 1992;53:119-22.
    3. 3971. Hollander E, McCarley A. Yohimbine treatment of sexual side effects induced by serotonin reuptake blockers. J Clin Psychiatry 1992;53:207-9.
    4. 17465. Kearney T, Tu N, Haller C. Adverse drug events associated with yohimbine-containing products: a retrospective review of the California Poison Control System reported cases. Ann Pharmacother 2010;44:1022-9. PubMed
    5. 86786. Adeniyi, A. A., Brindley, G. S., Pryor, J. P., and Ralph, D. J. Yohimbine in the treatment of orgasmic dysfunction. Asian J Androl 2007;9(3):403-407. PubMed
    6. 86801. Giampreti, A., Lonati, D., Locatelli, C., Rocchi, L., and Campailla, M. T. Acute neurotoxicity after yohimbine ingestion by a body builder. Clin Toxicol.(Phila) 2009;47(8):827-829. PubMed

    Gabapentin

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

  • An allergic reaction Worth acting on Additional detail

    Fever Bark

    “The yohimbine constituent of fever bark, when taken alone, causes allergic reactions (2,5,6,11,18). It is not known if this occurs with fever bark.”

    Fever Bark · Natural Medicines adverse-effect record, reported in fever.

    5 sources cited
    1. 2. Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
    2. 5. Foster S, Tyler VE. Tyler's Honest Herbal: A Sensible Guide to the Use of Herbs and Related Remedies. 3rd ed., Binghamton, NY: Haworth Herbal Press, 1993.
    3. 6. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
    4. 11. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
    5. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.

    Gabapentin

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

  • Mood changes or irritability / Anxiety or restlessness / Trouble sleeping Additional detail

    Fever Bark

    Recorded for Fever Bark in the same Natural Medicines adverse-effect record shown under Low mood above.

    Gabapentin

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

  • A stuffy or runny nose / Cough Additional detail

    Fever Bark

    “The yohimbine constituent of fever bark, when taken alone, may cause bronchospasm, tachynpea, cough, and rhinorrhea. The reserpine constituent of fever bark, when taken alone, may cause nasal congestion or bronchospasm (15,94328). It is not known if this occurs with fever bark.”

    Fever Bark · Natural Medicines adverse-effect record, reported in cough.

    5 sources cited
    1. 17465. Kearney T, Tu N, Haller C. Adverse drug events associated with yohimbine-containing products: a retrospective review of the California Poison Control System reported cases. Ann Pharmacother 2010;44:1022-9. PubMed
    2. 86825. Landis, E. and Shore, E. Yohimbine-induced bronchospasm. Chest 1989;96(6):1424. PubMed
    3. 86850. Charney, D. S., Heninger, G. R., and Sternberg, D. E. Assessment of alpha 2 adrenergic autoreceptor function in humans: effects of oral yohimbine. Life Sci 6-7-1982;30(23):2033-2041.
    4. 15. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
    5. 94328. Lobay D. Rauwolfia in the Treatment of Hypertension. Integr Med (Encinitas). 2015 Jun;14(3):40-6.

    Gabapentin

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

  • Stomach upset Additional detail

    Fever Bark

    “The yohimbine constituent of fever bark, when taken alone, causes salivation, diarrhea, and gastrointestinal distress. The reserpine constituent of fever bark, when taken alone, can cause peptic ulceration (17). It is not known if these effects occur with fever bark.”

    Fever Bark · Natural Medicines adverse-effect record, reported in diarrhea.

    6 sources cited
    1. 3970. Jacobsen FM. Fluoxetine-induced sexual dysfunction and an open trial of yohimbine. J Clin Psychiatry 1992;53:119-22.
    2. 17465. Kearney T, Tu N, Haller C. Adverse drug events associated with yohimbine-containing products: a retrospective review of the California Poison Control System reported cases. Ann Pharmacother 2010;44:1022-9. PubMed
    3. 49902. Abebe, W. An overview of herbal supplement utilization with particular emphasis on possible interactions with dental drugs and oral manifestations. J Dent.Hyg. 2003;77(1):37-46.
    4. 86780. Bagheri, H., Schmitt, L., Berlan, M., and Montastruc, J. L. Effect of 3 weeks treatment with yohimbine on salivary secretion in healthy volunteers and in depressed patients treated with tricyclic antidepressants. Br J Clin Pharmacol 1992;34(6):555-558. PubMed
    5. 86781. Bagheri, H., Bompart, G., Girolami, J. P., Montastruc, J. L., and Montastruc, P. Is yohimbine-induced increase in salivary secretion a kinin-dependent mechanism? Fundam.Clin Pharmacol 1992;6(1):17-20. PubMed
    6. 86786. Adeniyi, A. A., Brindley, G. S., Pryor, J. P., and Ralph, D. J. Yohimbine in the treatment of orgasmic dysfunction. Asian J Androl 2007;9(3):403-407. PubMed

    Gabapentin

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

  • Fever Additional detail

    Fever Bark

    “Orally, no adverse effects have been reported with fever bark; however, a thorough evaluation of safety outcomes has not been conducted. Theoretically, fever bark might cause the known adverse effects of its constituents, reserpine and yohimbine, and should be used with caution.”

    Fever Bark · Natural Medicines adverse-effect record, reported in fever.

    Gabapentin

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

Showing the 10 most notable of 14 shared effects — ranked by how unusual each one is, not just whether both lists mention it.

Reported for Fever Bark but not commonly for Gabapentin: heart failure, raised blood pressure, wheezing and muscle pain.

Effects for Gabapentin come from the ADVERSE REACTIONS section of its FDA label; effects for Fever Bark come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 361,481 voluntary FDA FAERS reports for Gabapentin 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.

From our Q&A

Questions About Fever Bark or Gabapentin

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Fever Bark or Gabapentin, 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 Gabapentin

This page covers Fever Bark only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Gabapentin page lists 106 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: 1,4-butanediol (major), Activated Charcoal (major), Beer (major), Gamma-hydroxybutyrate (ghb) (major) and Kava (major).

By severity: 7 major · 82 moderate · 17 minor.

From our pharmacist’s overview on the Gabapentin page

“Gabapentin (Neurontin, Gralise) calms overactive nerves, which means it already slows your nervous system down, and that is exactly what 78 of the 106 supplements on this list also do. So the dominant risk here is sedation stacked on sedation, extra drowsiness at best and dangerously slowed breathing at worst, and with seven entries ra…”

Reviewed by 2 · Jul 18, 2026

Open the Gabapentin interaction page

How much people look this up

Where Fever Bark and Gabapentin 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 Fever Bark
Steady interest

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

29 days ago today
Medication Gabapentin
Top 5%

#42 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 Fever Bark reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Fever Bark and Gabapentin 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 Fever Bark

What is Fever Bark?

Fever Bark
  • Fever
  • Diarrhea
  • Malaria (traditional)
  • Digestive complaints
  • Bitter tonic

Fever bark is the bark of the Australian tree Alstonia constricta, used in traditional medicine for fever, diarrhea, and infections. There is very little reliable human research to support these uses, and the bark contains potent alkaloids that may cause serious side effects. It is best avoided unless used under direct medical supervision.

Alstonia constricta · Apocynaceae · Bark · Bark powder, tincture, liquid extract, capsules

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

Fever Bark: dosing

There is no well-established, standardized dose for fever bark. Because the bark contains potent alkaloids that vary between products, a safe and effective dose has not been reliably determined in modern research.If a product is used at all, follow the directions on the label and do not exceed them.

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

Read the full Fever Bark monograph & all interactions
Medication

About Gabapentin

What Is Gabapentin Used For?

Brand names: Neurontin, Gralise

Gabapentin (brands include Neurontin, Relgaabi, Gabarone, Gralise, and Horizant) is primarily used to manage postherpetic neuralgia (PHN) — the nerve pain that lingers after a shingles outbreak — in adults. Neurontin, Relgaabi, Gabarone, and gabapentin capsules, tablets, and oral solution are also used as add-on therapy for partial onset seizures (a type of epilepsy) in adults and children aged 3 and older.

Horizant (gabapentin enacarbil extended-release tablet) has two specific approvals: treatment of moderate-to-severe primary restless legs syndrome (RLS) in adults, and management of postherpetic neuralgia in adults. Horizant is not recommended for people who need to sleep during the day and stay awake at night. Gralise is approved only for postherpetic neuralgia and cannot be substituted for other gabapentin products due to its different release profile.

Most-Reported Side Effects for Gabapentin

From FAERS, the FDA’s public side-effect reporting system (361,481 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Fatigue 24,972 reports
Nausea 22,728 reports
Diarrhea 18,114 reports
Headache 17,897 reports
Dizziness 16,238 reports
See full Gabapentin drug information
Keep checking

Other Drugs & Fever Bark

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

40Major
674Moderate
87Minor
2,028No known interaction
Major

40 interactions

Moderate

674 interactions

Showing 60 of 674 moderate interactions — see all 674 on the Fever Bark page.

Minor

87 interactions

Showing 60 of 87 minor interactions — see all 87 on the Fever Bark page.

No interaction 2,028 drugs checked — show the list
Evidence & sources

Fever Bark References

The 50 references that drive our Fever Bark 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. Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
  2. Foster S, Tyler VE. Tyler's Honest Herbal: A Sensible Guide to the Use of Herbs and Related Remedies. 3rd ed., Binghamton, NY: Haworth Herbal Press, 1993.
  3. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  4. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  5. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  6. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  7. Ellenhorn MJ, et al. Ellenhorn's Medical Toxicology: Diagnoses and Treatment of Human Poisoning. 2nd ed. Baltimore, MD: Williams & Wilkins, 1997.
  8. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  9. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  10. Sklar S, et al. Drug therapy screening system. Indianapolis, IN: First Data Bank 99.1-99. 2 eds.
  11. Teloken C, Rhoden EL, Sogari P, et al. Therapeutic effects of high dose yohimbine hydrochloride on organic erectile dysfunction. J Urol 1998;159:122-4. PubMed
  12. Jacobsen FM. Fluoxetine-induced sexual dysfunction and an open trial of yohimbine. J Clin Psychiatry 1992;53:119-22.
  13. Hollander E, McCarley A. Yohimbine treatment of sexual side effects induced by serotonin reuptake blockers. J Clin Psychiatry 1992;53:207-9.
  14. Kearney T, Tu N, Haller C. Adverse drug events associated with yohimbine-containing products: a retrospective review of the California Poison Control System reported cases. Ann Pharmacother 2010;44:1022-9. PubMed
  15. VandenBrink, B. M., Foti, R. S., Rock, D. A., Wienkers, L. C., and Wahlstrom, J. L. Prediction of CYP2D6 drug interactions from in vitro data: evidence for substrate-dependent inhibition. Drug Metab Dispos. 2012;40(1):47-53. 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 Fever Bark and Gabapentin Together: Common Questions

Is it safe to take Fever Bark with Gabapentin?
We do not list a known interaction between Fever Bark and Gabapentin. 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 Fever Bark and Gabapentin have any of the same side effects?
Yes — our sources link each of them separately to 10 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.
How was the Fever Bark and Gabapentin combination checked?
Interactions in our licensed database are recorded against drug classes. Gabapentin is filed under 4 classifications, and Fever Bark has documented interactions with 9 drug classes — none of Gabapentin's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Fever Bark interact with any other medications?
Yes. Fever Bark has 801 documented drug interactions in our database — Gabapentin is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Gabapentin interact with any supplements?
Yes. Gabapentin has documented interactions with 106 supplements in our database — Fever Bark is not one of them. The Gabapentin 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 Gabapentin and Fever Bark?

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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.