Drug & supplement interaction

Isopropylnorsynephrine + Acyclovir

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

No Known Interaction
The bottom line No known interaction

We found no known interaction between Isopropylnorsynephrine 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

Isopropylnorsynephrine 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 Isopropylnorsynephrine 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.

Isopropylnorsynephrine safety at a glance

Isopropylnorsyneph... overall Use caution It is a poorly studied synthetic stimulant with unknown long-term safety in humans.
Pregnancy Possibly Unsafe When used orally. Isopropylnorsynephrine has been associated with vomiting, hypertension, blurred vision, palpitations, and respiratory distress. When used in c... Read the full pregnancy detail
Breastfeeding Possibly Unsafe When used orally. Isopropylnorsynephrine has been associated with vomiting, hypertension, blurred vision, palpitations, and respiratory distress. When used in c... 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 Isopropylnorsynephrine? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Acyclovir

Interactions in our licensed database are recorded against drug classes, not just single drug names. Acyclovir is filed under 6 classifications — including organic anion transporter 1 (oat1) substrates, topical drugs, nephrotoxic drugs. Isopropylnorsynephrine has documented interactions with 2 drug classes — the most serious being antihypertensive drugs (moderate) and stimulant drugs (moderate) — and none of Acyclovir’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

Isopropylnorsynephrine Does Interact With Other Medications

Isopropylnorsynephrine has 344 moderate known drug interactions in our database — Acyclovir 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 Isopropylnorsynephrine

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

What to actually watch for

No Interaction Found — But Data Suggests Isopropylnorsynephrine 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.

  • Vomiting Additional detail

    Isopropylnorsynephrine

    “Orally and parenterally, isopropylnorsynephrine is generally regarded as unsafe.

    Serious Adverse Effects (Rare):

    Orally: Hypertension, palpitations, respiratory distress, and vomiting. Stroke and cardiac arrest have been reported when used with other stimulants or intensive exercise.”

    Isopropylnorsynephrine · Natural Medicines adverse-effect record, reported in acute respiratory distress syndrome (ards).

    “Orally, isopropylnorsynephrine has been associated with vomiting.”

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

    2 sources cited
    1. 21079. Venhuis B, Keizers P, van Riel A, de Kaste D. A cocktail of synthetic stimulants found in a dietary supplement associated with serious adverse events. Drug Test Anal. 2014 Jun;6(6):578-81. doi: 10.1002/dta.1664. Epub 2014 May 6. PubMed
    2. 104949. Cohen PA, Travis JC, Vanhee C, Ohana D, Venhuis BJ. Nine prohibited stimulants found in sports and weight loss supplements: deterenol, phenpromethamine (Vonedrine), oxilofrine, octodrine, beta-methylphenylethylamine (BMPEA), 1,3-dimethylamylamine (1,3-DMA

    Acyclovir

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

Reported for Isopropylnorsynephrine but not commonly for Acyclovir: shortness of breath, a fast or pounding heartbeat and raised blood pressure.

Effects for Acyclovir come from the ADVERSE REACTIONS section of its FDA label; effects for Isopropylnorsynephrine 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

Isopropylnorsynephrine in Pregnancy & Breastfeeding

Pregnancy And Lactation Possibly Unsafe

When used orally. Isopropylnorsynephrine has been associated with vomiting, hypertension, blurred vision, palpitations, and respiratory distress. When used in combination with stimulants or intensive exercise, isopropylnorsynephrine has been associated with adverse cardiovascular events such as stroke and cardiac arrest. 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 Isopropylnorsynephrine 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 Isopropylnorsynephrine 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 Isopropylnorsynephrine 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 Isopropylnorsynephrine as Part of a Dietary Supplement Product? Check It for Interactions

We hold 48 real supplement products containing Isopropylnorsynephrine, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Isopropylnorsynephrine. Even though Isopropylnorsynephrine 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 Isopropylnorsynephrine 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 Isopropylnorsynephrine
Steady interest

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

29 days ago today
Medication Acyclovir
Top 5%

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

What is Isopropylnorsynephrine?

  • Weight loss and fat burning
  • Pre-workout energy and stimulation
  • Topical fat reduction (creams and gels)
  • Appetite suppression
  • Athletic performance

Isopropylnorsynephrine is a synthetic stimulant chemically related to synephrine, marketed mainly in weight-loss and pre-workout supplements. It has very little human safety or effectiveness research, and as a stimulant it may raise heart rate and blood pressure, so caution is strongly advised. Talk with a pharmacist or doctor before using any product that contains it.

Synthetic compound (not a plant part) · Capsules, tablets, powders, and topical gels or creams (often in fat-loss and pre-workout products)

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

Isopropylnorsynephrine: dosing

There is no established or proven safe dose for isopropylnorsynephrine. No official health authority has set a recommended amount, and studies do not provide reliable dosing guidance.If a product contains it, follow the label instructions and do not exceed them.

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

Read the full Isopropylnorsynephrine 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 & Isopropylnorsynephrine

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

0Major
344Moderate
0Minor
2,485No known interaction
Moderate

344 interactions

Showing 60 of 344 moderate interactions — see all 344 on the Isopropylnorsynephrine page.

No interaction 2,485 drugs checked — show the list
Evidence & sources

Isopropylnorsynephrine References

The 3 references that drive our Isopropylnorsynephrine 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. Venhuis B, Keizers P, van Riel A, de Kaste D. A cocktail of synthetic stimulants found in a dietary supplement associated with serious adverse events. Drug Test Anal. 2014 Jun;6(6):578-81. doi: 10.1002/dta.1664. Epub 2014 May 6. PubMed
  2. Cohen PA, Travis JC, Vanhee C, Ohana D, Venhuis BJ. Nine prohibited stimulants found in sports and weight loss supplements: deterenol, phenpromethamine (Vonedrine), oxilofrine, octodrine, beta-methylphenylethylamine (BMPEA), 1,3-dimethylamylamine (1,3-DMA
  3. Anderson WG. The sympathomimetic activity of N-isopropyloctopamine in vitro. J Pharmacol Exp Ther 1983;225(3):553-8. DOI

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 Isopropylnorsynephrine and Acyclovir Together: Common Questions

Is it safe to take Isopropylnorsynephrine with Acyclovir?
We do not list a known interaction between Isopropylnorsynephrine 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 Isopropylnorsynephrine 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.
How was the Isopropylnorsynephrine and Acyclovir combination checked?
Interactions in our licensed database are recorded against drug classes. Acyclovir is filed under 6 classifications, and Isopropylnorsynephrine has documented interactions with 2 drug classes — none of Acyclovir'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 Isopropylnorsynephrine interact with any other medications?
Yes. Isopropylnorsynephrine has 344 documented drug interactions in our database — Acyclovir 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 Acyclovir interact with any supplements?
Yes. Acyclovir has documented interactions with 37 supplements in our database — Isopropylnorsynephrine 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 Isopropylnorsynephrine?

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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.