Drug & supplement interaction

Manna + Lactulose

Lactulose brand names: Cephulac, Constulose, Constilac, Evalose, Laxilose, and others.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Manna and Lactulose 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.

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Interaction report

Manna and Lactulose

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 Lactulose and Manna 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.

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.

Manna safety at a glance

Manna overall Use caution Generally mild but can cause loose stools, gas, and cramping, especially at higher amounts.
Pregnancy Use caution Not well studied in pregnancy; use only under medical supervision.
Breastfeeding Use caution Little safety information exists, so caution is advised while breastfeeding.

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

Still wondering about combining Lactulose and Manna? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Lactulose

Interactions in our licensed database are recorded against drug classes, not just single drug names. Lactulose is filed under a single classification — oral drugs. Manna has documented interactions with 4 drug classes — the most serious being digoxin (lanoxin) (moderate), diuretic drugs (moderate) and stimulant laxatives (moderate) — and none of Lactulose’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Manna Does Interact With Other Medications

Manna has 99 moderate known drug interactions in our database — Lactulose isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Manna

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

What to actually watch for

No Interaction Found — But Data Suggests Manna and Lactulose 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.

  • Bloating or gas / Nausea reported in 6.9% of FDA reports for Lactulose Additional detail

    Manna

    “Orally, manna has been reported to cause flatulence and nausea (2,18).”

    Manna · Natural Medicines adverse-effect record, reported in flatulence.

    2 sources cited
    1. 2. Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
    2. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.

    Lactulose

    Listed in the ADVERSE REACTIONS section of the FDA label for Lactulose, and in voluntary FDA adverse-event reports. Read the label on DailyMed ›

Effects for Lactulose come from the ADVERSE REACTIONS section of its FDA label; effects for Manna come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 38,211 voluntary FDA FAERS reports for Lactulose that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Overlapping uses

What Lactulose Is Prescribed For, and What Manna Has Been Studied For

These two come up together because they touch the same health topic — not because they do the same job. Lactulose is a prescription medicine with approved uses on its FDA label. Manna is a supplement: what follows is what researchers have looked at it for, and how strong that evidence is.

Lactulose is prescribed for: Lactulose is used for two main purposes, depending on the product. Constulose (oral solution) and Kristalose (powder for oral solution) are indicated for the treatment of constipation, helping increase the number of bowel movements in people with chronic constipation. Enulose, Generlac, and Lactulose oral/rectal solutions are used to prevent and treat portal-systemic encephalopathy (PSE) — a condition where the liver cannot clear ammonia from the blood, causing confusion and even coma. These products work to lower blood ammonia levels and improve mental function in affected patients.

Manna has been studied for:

  • Constipation studied, not established Manna has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Manna for constipation

    Although there has been interest in using oral manna for constipation, there is insufficient reliable information about the clinical effects of manna for this purpose.

Effectiveness ratings and the research summaries above are the verbatim record from the Natural Medicines database, which grades evidence from “Effective” down to “Insufficient Reliable Evidence To Rate”. A rating below the top of that scale means researchers have looked at it — not that it works, and never that it can stand in for a prescribed medicine. Do not stop or replace Lactulose on your own; if you are taking Manna for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

From our Q&A

Questions About Manna or Lactulose

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Manna or Lactulose, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Lactulose

This page covers Manna only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Lactulose page lists 17 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Coffee Charcoal (moderate), European Mandrake (moderate), Glucomannan (moderate) and Guar Gum (moderate).

By severity: 1 major · 7 moderate · 9 minor.

Open the Lactulose interaction page

One more smart check

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

We hold 27 real supplement products containing Manna, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Manna. Even though Manna itself has no known interaction with Lactulose, 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 Manna and Lactulose 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 Manna
Top half

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

29 days ago today
Medication Lactulose
Steady interest

#1,868 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 Manna reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Manna and Lactulose 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 Manna

What is Manna?

Manna
  • Gentle constipation relief
  • Mild laxative for children and elderly
  • Natural sweetener
  • Occasional bowel softening

Manna is the dried, sweet sap of the flowering ash tree (Fraxinus ornus) and is best known as a gentle, mild laxative because it contains a sugar alcohol called mannitol. It is generally considered mild and is sometimes used for occasional constipation, but high-quality modern studies are limited, so talk with your pharmacist or doctor before using it.

Fraxinus ornus · Oleaceae · Dried sap (exudate) from the bark and stems · Dried flakes or pieces, syrup, powder, and as an ingredient in laxative products

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

Manna: dosing

There is no official standardized dose of manna for supplement use. Amounts have traditionally varied based on the person's age and how strong a laxative effect is needed, with smaller amounts used for children.If you choose to use a manna product, follow the directions on the label and start with the lowest amount.

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

Read the full Manna monograph & all interactions
Medication

About Lactulose

What Is Lactulose Used For?

Brand names: Cephulac, Constulose, Constilac, Evalose, Laxilose, Enulose, Cholac, Heptalac, Generlac, Acilac, Chronulac, Duphalac

Lactulose is used for two main purposes, depending on the product. Constulose (oral solution) and Kristalose (powder for oral solution) are indicated for the treatment of constipation, helping increase the number of bowel movements in people with chronic constipation.

Enulose, Generlac, and Lactulose oral/rectal solutions are used to prevent and treat portal-systemic encephalopathy (PSE) — a condition where the liver cannot clear ammonia from the blood, causing confusion and even coma. These products work to lower blood ammonia levels and improve mental function in affected patients.

Most-Reported Side Effects for Lactulose

From FAERS, the FDA’s public side-effect reporting system (38,211 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Nausea 2,627 reports
Constipation 2,569 reports
Fall 2,304 reports
Vomiting 2,143 reports
Fatigue 2,099 reports
See full Lactulose drug information
Keep checking

Other Drugs & Manna

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

0Major
99Moderate
0Minor
2,730No known interaction
Moderate

99 interactions

Showing 60 of 99 moderate interactions — see all 99 on the Manna page.

No interaction 2,730 drugs checked — show the list
Evidence & sources

Manna References

The 3 references that drive our Manna 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. Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
  2. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  3. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.

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 Manna and Lactulose Together: Common Questions

Is it safe to take Manna with Lactulose?
We do not list a known interaction between Manna and Lactulose. 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 Manna and Lactulose 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.
Are Manna and Lactulose used for the same thing?
They overlap in purpose, which usually means the real question is whether you need both rather than whether they are safe together. This page lists the shared uses and how strong the evidence is for Manna in each. That is a conversation for your prescriber, especially if Lactulose is being adjusted to a target.
How was the Manna and Lactulose combination checked?
Interactions in our licensed database are recorded against drug classes. Lactulose is filed under 1 classification, and Manna has documented interactions with 4 drug classes — none of Lactulose's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Manna interact with any other medications?
Yes. Manna has 99 documented drug interactions in our database — Lactulose is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Lactulose interact with any supplements?
Yes. Lactulose has documented interactions with 17 supplements in our database — Manna is not one of them. The Lactulose interaction page linked on this page lists every one, ranked by severity.

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

Still Have a Question About Lactulose and Manna?

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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.