Drug & supplement interaction

Casein Peptides + Reserpine

Reserpine brand names: Serpasil, Sandril.

Moderate Interaction
Medically reviewed by · Updated September 2026
The bottom line Moderate

Casein Peptides has a moderate interaction with Reserpine. Theoretically, combining these casein peptides with antihypertensive drugs might increase the risk of hypotension.

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

Casein Peptides and Reserpine

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

Moderate

ANTIHYPERTENSIVE DRUGS

Why this applies to Reserpine

Reserpine falls under ANTIHYPERTENSIVE DRUGS — the group Casein Peptides interacts with.

Theoretically, combining these casein peptides with antihypertensive drugs might increase the risk of hypotension.
Clinical research shows that some casein peptides, including the lactotripeptides isoleucine-proline-proline (IPP) and valine-proline-proline (VPP), can modestly reduce blood pressure in patients with hypertension.
Severity Moderate Likelihood Probable Evidence B

Interaction 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..

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

Here's the simple version: reserpine already works hard to bring your blood pressure down by calming your nervous system and relaxing your blood vessels. Casein peptides may nudge blood pressure down a little too, possibly by softening the same hormone system (ACE and the renin-angiotensin pathway) that some pressure medicines target. Stack the two and your numbers could dip lower than you expect.

If that happens, you might feel dizzy, lightheaded, tired, or faint, especially when standing up quickly. The blood pressure effect of these peptides is modest and the evidence is only fair, so this isn't a reason to panic. But since reserpine is powerful, it's smart to mention the supplement to your pharmacist or doctor and keep an eye on your readings.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Cicero AFG, Aubin F, Azais-Braesco V, Borghi C. Do the lactotripeptides isoleucine-proline-proline and valine-proline-proline reduce systolic blood pressure in European subjects? A meta-analysis of randomized controlled trials. Am J Hypertens. 2013;26(3): PubMed
  2. Fekete AA, Givens DA, Lovegrove JA. Casein-derived lactotripeptides reduce systolic and diastolic blood pressure in a meta-analysis of randomised clinical trials. Nutrients. 2015;7(1):659-81. PubMed
  3. Qin LQ, Xu JY, Dong JY, Zhao Y, van Bladeren P, Zhang W. Lactotripeptides intake and blood pressure management: a meta-analysis of randomised controlled clinical trials. Nutr Metab Cardiovasc Dis. 2013;23(5):395-402. PubMed
  4. Turpeinen AM, Järvenpää S, Kautiainen H, Korpela R, Vapaatalo H. Antihypertensive effects of bioactive tripeptides-a random effects meta-analysis. Ann Med. 2013;45(1):51-6. 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

Casein Peptides Also Interacts With Other Medications

Casein Peptides has 171 moderate known drug interactions in our database — the Reserpine one above is one of them. If you take anything else, check it against the full list below.

Moderate 171 No known interaction 2,659 (incl. Reserpine)
Taking anything else?

Check Another of Your Medications Against Casein Peptides

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

Everything else you take

See Every Supplement That Interacts With Reserpine

This page covers Casein Peptides only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Reserpine page lists 138 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), American Mistletoe (major), Tyramine (major) and Adrafinil (moderate).

By severity: 4 major · 113 moderate · 21 minor.

From our pharmacist’s overview on the Reserpine page

“Reserpine (Serpasil, Sandril) lowers blood pressure, and the 138 supplements and herbs listed here merit real vigilance, four of them rated major. Most pull in one of two directions: many common supplements lower pressure on their own and can add to reserpine's effect, dropping it too far, while a smaller group raises pressure and work…”

Reviewed by 2 · Jul 18, 2026

Open the Reserpine interaction page

One more smart check

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

We hold 82 real supplement products containing Casein Peptides, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Casein Peptides. Your product may carry other ingredients that interact with Reserpine too, on top of Casein Peptides — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Casein Peptides and Reserpine 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 Casein Peptides
Steady interest

#1,118 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Reserpine
Steady interest

#1,680 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 Casein Peptides

What is Casein Peptides?

  • High blood pressure
  • Stress and relaxation
  • Sleep support
  • General wellness/protein supplement

Casein peptides are small protein fragments made from milk casein, often studied for mild blood pressure support and relaxation. The evidence is limited and mostly modest, so they should not replace proven treatments. People with milk allergy should avoid them, and anyone with a health condition should check with a pharmacist or doctor first.

Read the full Casein Peptides monograph & all interactions
Medication

About Reserpine

What Is Reserpine Used For?

Brand names: Serpasil, Sandril

  • Reserpine is used to treat high blood pressure. It also is used to treat severe agitation in patients with mental disorders. Reserpine is in a class of medications called rauwolfia alkaloids. It works by slowing the activity of the nervous system, causing the heartbeat to slow and the blood vessels to relax.

  • High blood pressure is a common condition and when not treated, can cause damage to the brain, heart, blood vessels, kidneys and other parts of the body. Damage to these organs may cause heart disease, a heart attack, heart failure, stroke, kidney failure, loss of vision, and other problems. In addition to taking medication, making lifestyle changes will also help to control your blood pressure. These changes include eating a diet that is low in fat and salt, maintaining a healthy weight, exercising at least 30 minutes most days, not smoking, and using alcohol in moderation.

See full Reserpine drug information
Keep checking

Other Drugs & Casein Peptides

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

0Major
171Moderate
0Minor
2,658No known interaction
171 Moderate 2,658 No interaction
Moderate

171 interactions

Showing 60 of 171 moderate interactions — see all 171 on the Casein Peptides page.

No interaction 2,658 drugs checked — show the list

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

Showing the 60 most looked-up of 2,658 medications checked with no known interaction — see the full Casein Peptides list.

See the full Casein Peptides interactions page
See every supplement checked against Reserpine, ranked by severity
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

Keep exploring
Casein Peptides monograph › Uses, safety, and every drug interaction in one place Reserpine supplement interactions › Every supplement checked against Reserpine, ranked by severity Reserpine drug information › The full plain-English guide to this medication Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Casein Peptides and Reserpine Together: Common Questions

Can you take Casein Peptides with Reserpine?
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 Casein Peptides and Reserpine 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

Still Have a Question About Reserpine and Casein Peptides?

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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.