Drug & supplement interaction

Purple Nut Sedge + Fluphenazine

Fluphenazine brand names: Prolixin, Permitil, Fluphenazine.

Moderate Interaction
The bottom line Moderate

Purple Nut Sedge has a moderate interaction with Fluphenazine. In vitro, purple nut sedge dose-dependently inhibits acetylcholinesterase (AChE).

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Purple Nut Sedge and Fluphenazine

Here is the interaction we found between these two, with the evidence behind it.

Moderate

ANTICHOLINERGIC DRUGS

Why this applies to Fluphenazine

Fluphenazine falls under ANTICHOLINERGIC DRUGS — the group Purple Nut Sedge interacts with.

In vitro, purple nut sedge dose-dependently inhibits acetylcholinesterase (AChE). Theoretically, concurrent use of anticholinergic drugs and purple nut sedge might decrease the effectiveness of purple nut sedge or the anticholinergic agent.
Some anticholinergic drugs include atropine, benztropine (Cogentin), biperiden (Akineton), procyclidine (Kemadrin), and trihexyphenidyl (Artane).
Severity Moderate Likelihood Possible Evidence D

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the gist with fluphenazine and purple nut sedge. Fluphenazine has some anticholinergic activity, meaning part of how it works is by quieting the chemical messenger acetylcholine. In lab dishes, purple nut sedge does the opposite, blocking the enzyme that breaks acetylcholine down, so more of it sticks around. In theory, the two could partly cancel each other out, which might slightly soften fluphenazine's effect or work against the supplement.

I want to be honest though: this is based only on test-tube and animal data, not real patients, so it's more of a theoretical caution than a proven problem. I wouldn't lose sleep over it, but since fluphenazine controls serious symptoms, it's worth a quick chat with your pharmacist or doctor before adding the supplement.

References
  1. Sharma R, Gupta R. Cyperus rotundus extract inhibits acetylcholinesterase activity from animal and plants as well as inhibits germination and seedling growth in wheat and tomato. Life Sci. 2007;80(24-25):2389-2392. PubMed

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Purple Nut Sedge Also Interacts With Other Medications

Purple Nut Sedge has 423 moderate known drug interactions in our database — the Fluphenazine one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Purple Nut Sedge

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

Everything else you take

See Every Supplement That Interacts With Fluphenazine

This page covers Purple Nut Sedge only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Fluphenazine page lists 148 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Henbane (major), Indian Snakeroot (major), Rauvolfia Vomitoria (major) and Scopolia (major).

By severity: 5 major · 109 moderate · 34 minor.

From our pharmacist’s overview on the Fluphenazine page

“Take real care with supplements while on fluphenazine (Prolixin), an antipsychotic used mainly for schizophrenia. Five of the 148 ingredients on file rate major: herbs like henbane that stack anticholinergic side effects (dry mouth, blurred vision, confusion) onto a drug already prone to them, two rauwolfia plants that can intensify it…”

Reviewed by 2 · Jul 18, 2026

Open the Fluphenazine interaction page

How much people look this up

Where Purple Nut Sedge and Fluphenazine 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 Purple Nut Sedge
Top half

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

29 days ago today
Medication Fluphenazine
Top half

#1,012 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.

Supplement

About Purple Nut Sedge

What is Purple Nut Sedge?

  • Digestive upset and bloating
  • Menstrual cramps and irregular periods
  • Fever and inflammation
  • Skin and weight-related concerns
  • Antimicrobial uses

Purple nut sedge (Cyperus rotundus) is a common weed whose tubers have a long history in Ayurvedic, Chinese, and other traditional medicine systems, mostly for digestive and menstrual complaints. Modern human evidence is very limited, so its benefits remain unproven. If you want to try it, talk with a pharmacist or doctor first, and avoid it during pregnancy and breastfeeding.

Read the full Purple Nut Sedge monograph & all interactions
Medication

About Fluphenazine

What Is Fluphenazine Used For?

Brand names: Prolixin, Permitil, Fluphenazine

Fluphenazine hydrochloride tablets and oral solution are indicated for the management of psychotic disorders. Fluphenazine Hydrochloride Injection is also used for psychotic disorders and can bridge patients to oral therapy.

Fluphenazine Decanoate Injection is a long-acting form specifically intended for patients who need extended antipsychotic treatment — for example, those with chronic schizophrenia who benefit from a single injection that can last up to four weeks or longer. It is not approved for behavioral problems related to intellectual disability, and it is not approved for dementia-related psychosis in elderly patients.

See full Fluphenazine drug information
Keep checking

Other Drugs & Purple Nut Sedge

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

0Major
423Moderate
0Minor
2,406No known interaction
Moderate

423 interactions

Showing 60 of 423 moderate interactions — see all 423 on the Purple Nut Sedge page.

No interaction 2,406 drugs checked — show the list
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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Pharmacist Counseling Corner

Taking Purple Nut Sedge and Fluphenazine Together: Common Questions

Can you take Purple Nut Sedge with Fluphenazine?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Purple Nut Sedge and Fluphenazine interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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

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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.