Drug & supplement interaction

Guava + Insulin Aspart

Insulin Aspart brand name: Fiasp.

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

Guava has a moderate interaction with Insulin Aspart. Theoretically, concomitant use with antidiabetes drugs might have additive effects and increase the risk of hypoglycemia.

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

Guava and Insulin Aspart

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

Moderate

ANTIDIABETES DRUGS

Why this applies to Insulin Aspart

Insulin Aspart falls under ANTIDIABETES DRUGS — the group Guava interacts with.

Theoretically, concomitant use with antidiabetes drugs might have additive effects and increase the risk of hypoglycemia. Animal research shows that guava leaf extract or guava fruit can have hypoglycemic effects. Monitor blood glucose levels closely. Medication dose adjustments may be necessary. Some antidiabetes drugs include glimepiride (Amaryl), glyburide (Diabeta, Glynase PresTab, Micronase), insulin, metformin, pioglitazone (Actos), rosiglitazone (Avandia), and others.
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 simple version: insulin aspart (Fiasp) already does one job very well, which is to bring your blood sugar down fast around mealtimes. Some early lab and animal studies hint that guava leaf may also nudge blood sugar lower. Stack those two together and the worry is an additive drop, meaning your sugar could fall further or faster than you expect.

That can show up as shakiness, sweating, dizziness, a racing heart, or confusion, which are the classic signs of a low. To be clear, this is mostly theoretical and based on weak evidence, so I'm not telling you to avoid guava. Eating the fruit as food is unlikely to be a big deal. If you want to use concentrated guava leaf supplements, check your sugars closely and talk with your doctor or pharmacist first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Gutiérrez RM, Mitchell S, Solis RV. Psidium guajava: a review of its traditional uses, phytochemistry and pharmacology. J Ethnopharmacol. 2008;117(1):1-27. 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

Guava Also Interacts With Other Medications

Guava has 85 moderate known drug interactions in our database — the Insulin Aspart one above is one of them. If you take anything else, check it against the full list below.

Moderate 85 No known interaction 2,745 (incl. Insulin Aspart)
Taking anything else?

Check Another of Your Medications Against Guava

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

Everything else you take

See Every Supplement That Interacts With Insulin Aspart

This page covers Guava only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Insulin Aspart page lists 239 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Siberian Cocklebur (major), Acai (moderate), African Wild Potato (moderate), Agaricus Mushroom (moderate) and Agmatine (moderate).

By severity: 1 major · 208 moderate · 30 minor.

From our pharmacist’s overview on the Insulin Aspart page

“Every one of the 239 supplements listed for insulin aspart (Fiasp) touches the same thing the drug exists to manage, blood sugar, so this list warrants genuine care rather than a quick skim. Most entries add to insulin's glucose-lowering effect, raising the risk of hypoglycemia, and with a rapid-acting mealtime insulin a low can become…”

Reviewed by 2 · Jul 18, 2026

Open the Insulin Aspart interaction page

One more smart check

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

We hold 484 real supplement products containing Guava, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Guava. Your product may carry other ingredients that interact with Insulin Aspart too, on top of Guava — 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 Guava and Insulin Aspart 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 Guava
Top half

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

29 days ago today
Medication Insulin Aspart
Steady interest

#1,660 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 Guava

What is Guava?

  • Diarrhea and digestive upset
  • Blood sugar support
  • Cholesterol support
  • Wound and skin care
  • Cough and sore throat

Guava is a tropical fruit tree whose leaves and fruit have a long history of folk use for diarrhea, blood sugar, and general wellness. The fruit is a nutritious food rich in vitamin C, but evidence for guava leaf supplements treating specific health conditions is limited and mostly early. If you want to try guava leaf products, talk with your pharmacist or doctor first, especially if you take medicines or have a health condition.

Read the full Guava monograph & all interactions
Medication

About Insulin Aspart (rDNA Origin) Injection

What Is Insulin Aspart (rDNA Origin) Injection Used For?

Brand name: Fiasp

Insulin aspart is used to improve blood sugar (glucose) control in people with diabetes mellitus. It is approved for both type 1 and type 2 diabetes in adults, and for diabetes mellitus in pediatric patients.

Insulin Aspart Protamine and Insulin Aspart Mix 70/30 is a pre-mixed product that combines a rapid-acting and an intermediate-acting insulin aspart. It is approved to improve blood sugar control in adult patients with diabetes mellitus. It is not recommended for treating diabetic ketoacidosis, and because its ratio of rapid-acting to intermediate-acting insulin is fixed, it does not allow for separate mealtime versus background dose adjustments.

See full Insulin Aspart (rDNA Origin) Injection drug information
Keep checking

Other Drugs & Guava

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

0Major
85Moderate
0Minor
2,744No known interaction
85 Moderate 2,744 No interaction
Moderate

85 interactions

Showing 60 of 85 moderate interactions — see all 85 on the Guava page.

No interaction 2,744 drugs checked — show the list

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

Showing the 60 most looked-up of 2,744 medications checked with no known interaction — see the full Guava list.

See the full Guava interactions page
See every supplement checked against Insulin Aspart, 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
Guava monograph › Uses, safety, and every drug interaction in one place Insulin Aspart supplement interactions › Every supplement checked against Insulin Aspart, ranked by severity Insulin Aspart (rDNA Origin) Injection 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 Guava and Insulin Aspart Together: Common Questions

Can you take Guava with Insulin Aspart?
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 Guava and Insulin Aspart 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 Insulin Aspart and Guava?

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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.