Drug & supplement interaction

Aloe + Caffeine (OTC drug)

Caffeine (OTC drug) brand names: Vivarin, Overtime, Molie.

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

Aloe has a minor interaction with Caffeine (OTC drug). Theoretically, aloe might decrease the levels and clinical effects of CYP1A2 substrates.

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

Aloe and Caffeine (OTC drug)

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

Minor

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES

Why this applies to Caffeine (OTC drug)

Caffeine (OTC drug) falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES — the group Aloe interacts with.

Theoretically, aloe might decrease the levels and clinical effects of CYP1A2 substrates.
In vitro research shows that aloe extract induces CYP1A2 enzymes.
Severity Minor 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: your body clears caffeine using a liver enzyme called CYP1A2. Lab studies hint that aloe taken by mouth might speed up that enzyme. If that happened in people, your caffeine could get broken down a little faster, meaning the perk you expect (more alertness, less drowsiness) might wear off sooner or feel a bit weaker.

Honestly, I wouldn't lose sleep over this one. The evidence is only from test-tube and animal work, the interaction is rated minor, and aloe gel on your skin or culinary amounts aren't likely to do anything. If you're taking concentrated oral aloe regularly and notice your caffeine isn't doing much, mention it to your pharmacist or doctor.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Haron MH, Dale O, Martin K, et al. Evaluation of the Herb-Drug Interaction Potential of Commonly Used Botanicals on the US Market with Regard to PXR- and AhR-Mediated Influences on CYP3A4 and CYP1A2. J Diet Suppl 2022. 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

Aloe Also Interacts With Other Medications

Aloe has 1 major, 304 moderate, 155 minor known drug interactions in our database — the Caffeine (OTC drug) one above is one of them. If you take anything else, check it against the full list below.

Major 1 Moderate 304 Minor 155 No known interaction 2,370 (incl. Caffeine (OTC drug))
Taking anything else?

Check Another of Your Medications Against Aloe

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

Everything else you take

See Every Supplement That Interacts With Caffeine (OTC drug)

This page covers Aloe only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Caffeine (OTC drug) page lists 208 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Ephedra (major), Grapefruit (major), Peyote (major) and Rauvolfia Vomitoria (major).

By severity: 7 major · 155 moderate · 46 minor.

From our pharmacist’s overview on the Caffeine (OTC drug) page

“The person swallowing a caffeine pill like Vivarin to power through a shift is often the same person drinking coffee, taking an herbal energy blend, or scooping pre-workout powder, and that overlap is exactly where the danger sits. Seven of the 208 supplement ingredients on file carry a major rating, and those seven are worth understan…”

Reviewed by 2 · Jul 18, 2026

Open the Caffeine (OTC drug) interaction page

One more smart check

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

We hold 1,978 real supplement products containing Aloe, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Aloe. Your product may carry other ingredients that interact with Caffeine (OTC drug) too, on top of Aloe — 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 Aloe and Caffeine (OTC drug) 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 Aloe
Top 10%

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

29 days ago today
Medication Caffeine (OTC drug)
Top 25%

#444 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 Aloe

What is Aloe?

Aloe
  • Minor burns and skin irritation
  • Wound healing
  • Constipation
  • Skin hydration and moisturizing
  • Digestive complaints
  • Hair and scalp care

Aloe vera gel is widely used on the skin for minor burns and irritation, and some research suggests it may help. Aloe latex (the yellow part) is a strong laxative that can cause cramping and is not considered safe for regular use. Talk to your pharmacist or doctor before taking aloe by mouth, and avoid oral aloe during pregnancy.

Read the full Aloe monograph & all interactions
Keep checking

Other Drugs & Aloe

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

1Major
304Moderate
155Minor
2,369No known interaction
1 Major 304 Moderate 155 Minor 2,369 No interaction
Major

1 interaction

Moderate

304 interactions

Showing 60 of 304 moderate interactions — see all 304 on the Aloe page.

Minor

155 interactions

Showing 60 of 155 minor interactions — see all 155 on the Aloe page.

No interaction 2,369 drugs checked — show the list

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

Showing the 60 most looked-up of 2,369 medications checked with no known interaction — see the full Aloe list.

See the full Aloe interactions page
See every supplement checked against Caffeine (OTC drug), 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
Aloe monograph › Uses, safety, and every drug interaction in one place Caffeine (OTC drug) supplement interactions › Every supplement checked against Caffeine (OTC drug), 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 Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Aloe and Caffeine (OTC drug) Together: Common Questions

Can you take Aloe with Caffeine (OTC drug)?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Aloe and Caffeine (OTC drug) interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

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

Still Have a Question About Caffeine (OTC drug) and Aloe?

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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.