Drug & supplement interaction

Parsnip + Trastuzumab-Pkrb

Trastuzumab-Pkrb brand name: Herzuma.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 13, 2026
The bottom line No known interaction

We found no known interaction between Parsnip and Trastuzumab-Pkrb 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.

Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Parsnip and Trastuzumab-Pkrb

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 Trastuzumab-Pkrb and Parsnip 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 Parsnip at all — not against Trastuzumab-Pkrb, 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.

Parsnip safety at a glance

Parsnip overall Use caution Safe as a food, but its leaves, sap, and seeds contain compounds that can cause skin reactions with sun exposure.
Pregnancy Use caution Fine as a normal food, but avoid concentrated supplement or medicinal amounts due to lack of safety data.
Breastfeeding Use caution Safe as a food, but the safety of medicinal or concentrated amounts is not known.

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

Still wondering about combining Trastuzumab-Pkrb and Parsnip? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

No Interaction Found — But Data Suggests Parsnip and Trastuzumab-Pkrb 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.

  • Swelling Additional detail

    Parsnip

    “Topically, contact dermatitis and phototoxic reactions, including skin blisters and later hyperpigmentation, have occurred following exposure to parsnip sap or fresh parsnip root and exposure to sunlight or UV-A light from a sunbed. Light-skinned people may be particularly susceptible to these reactions.

    A case report describes a 51-year-old male who developed rashes on his hands after preparing parsnip.”

    Parsnip · Natural Medicines adverse-effect record, reported in dermatitis.

    6 sources cited
    1. 10071. Ivie GW, Holt DL, Ivey MC. Natural toxicants in human foods: psoralens in raw and cooked parsnip root. Science 1981;213:909-10.. PubMed
    2. 68289. Lutchman, L., Inyang, V., and Hodgkinson, D. Phytophotodermatitis associated with parsnip picking. J.Accid.Emerg.Med. 1999;16(6):453-454. PubMed
    3. 68291. Aberer, W. Occupational dermatitis from organically grown parsnip (Pastinaca sativa L.). Contact Dermatitis 1992;26(1):62.
    4. 68295. Bang, Pedersen N. and Pla Arles, U. B. Phototoxic reaction to parsnip and UV-A sunbed. Contact Dermatitis 1998;39(2):97. PubMed
    5. 111192. White JML, Pink AE. English Sunday lunch dermatitis: Allergic contact dermatitis to parsnip, carrot, fennel (and ivy). Contact Dermatitis. 2020 Oct;83(4):317-8. PubMed
    6. 111193. Lafon A, Boulard C. Perioral phytophotodermatitis induced by parsnip mash. Contact Dermatitis. 2020 Oct;83(4):318-9. PubMed

    Trastuzumab-Pkrb

    Listed in the ADVERSE REACTIONS section of the FDA label for Trastuzumab-Pkrb. Read the label on DailyMed ›

  • A skin rash Additional detail

    Parsnip

    “Topically, contact dermatitis and phototoxic reactions (including skin blisters) are possible following exposure to parsnip sap or fresh parsnip root and exposure to sunlight. Allergic contact dermatitis can occur but is rare.”

    Parsnip · Natural Medicines adverse-effect record, reported in dermatitis.

    4 sources cited
    1. 10071. Ivie GW, Holt DL, Ivey MC. Natural toxicants in human foods: psoralens in raw and cooked parsnip root. Science 1981;213:909-10.. PubMed
    2. 68289. Lutchman, L., Inyang, V., and Hodgkinson, D. Phytophotodermatitis associated with parsnip picking. J.Accid.Emerg.Med. 1999;16(6):453-454. PubMed
    3. 68291. Aberer, W. Occupational dermatitis from organically grown parsnip (Pastinaca sativa L.). Contact Dermatitis 1992;26(1):62.
    4. 68295. Bang, Pedersen N. and Pla Arles, U. B. Phototoxic reaction to parsnip and UV-A sunbed. Contact Dermatitis 1998;39(2):97. PubMed

    Trastuzumab-Pkrb

    Listed in the ADVERSE REACTIONS section of the FDA label for Trastuzumab-Pkrb. Read the label on DailyMed ›

Effects for Trastuzumab-Pkrb come from the ADVERSE REACTIONS section of its FDA label; effects for Parsnip 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.

One more smart check

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

We hold 38 real supplement products containing Parsnip, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Parsnip. Even though Parsnip itself has no known interaction with Trastuzumab-Pkrb, 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 Parsnip and Trastuzumab-Pkrb 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 Parsnip
Steady interest

#1,267 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Trastuzumab-Pkrb
Steady interest

#2,471 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 Parsnip reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Parsnip and Trastuzumab-Pkrb 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 Parsnip

What is Parsnip?

  • Digestive support
  • Mild diuretic ('water pill') effect
  • Nutritional/dietary fiber source
  • Traditional kidney and urinary support
  • General wellness

Parsnip is mainly a nutritious root vegetable that is safe and healthy as part of a normal diet. Its use as a concentrated supplement or herbal remedy is not well studied, and certain parts of the plant can make skin very sensitive to sunlight. Talk to your pharmacist or doctor before using parsnip in any medicinal or high-dose form.

Pastinaca sativa · Apiaceae · Root, leaves, seeds, and essential oil · Whole root (food), cooked vegetable, juice, dried seeds, and rarely supplements or essential oil

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

Parsnip: dosing

There is no established medicinal dose for parsnip. As a food, it is simply eaten as a vegetable in normal serving amounts.If you choose to use a parsnip supplement, juice, or extract, there is no standardized dose backed by research.

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

Read the full Parsnip monograph & all interactions
Keep checking

Other Drugs & Parsnip

Browse every other medication we’ve checked against Parsnip — 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
2,829 No interaction
No interaction 2,829 drugs checked — show the list

We also checked Parsnip against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,829 medications checked with no known interaction — see the full Parsnip list.

See the full Parsnip interactions page
See every supplement checked against Trastuzumab-Pkrb, ranked by severity
Evidence & sources

Parsnip References

The 6 references that drive our Parsnip 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. Ivie GW, Holt DL, Ivey MC. Natural toxicants in human foods: psoralens in raw and cooked parsnip root. Science 1981;213:909-10.. PubMed
  2. Lutchman, L., Inyang, V., and Hodgkinson, D. Phytophotodermatitis associated with parsnip picking. J.Accid.Emerg.Med. 1999;16(6):453-454. PubMed
  3. Aberer, W. Occupational dermatitis from organically grown parsnip (Pastinaca sativa L.). Contact Dermatitis 1992;26(1):62.
  4. Bang, Pedersen N. and Pla Arles, U. B. Phototoxic reaction to parsnip and UV-A sunbed. Contact Dermatitis 1998;39(2):97. PubMed
  5. White JML, Pink AE. English Sunday lunch dermatitis: Allergic contact dermatitis to parsnip, carrot, fennel (and ivy). Contact Dermatitis. 2020 Oct;83(4):317-8. PubMed
  6. Lafon A, Boulard C. Perioral phytophotodermatitis induced by parsnip mash. Contact Dermatitis. 2020 Oct;83(4):318-9. 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 Parsnip and Trastuzumab-Pkrb Together: Common Questions

Is it safe to take Parsnip with Trastuzumab-Pkrb?
We do not list a known interaction between Parsnip and Trastuzumab-Pkrb. 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 Parsnip and Trastuzumab-Pkrb have any of the same side effects?
Yes — our sources link each of them separately to 2 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.

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

Where next

Keep Exploring

Parsnip monograph Uses, safety profile, and every drug interaction in one place Trastuzumab-Pkrb supplement interactions Every supplement checked against Trastuzumab-Pkrb, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 6 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Trastuzumab-Pkrb and Parsnip?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.