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Lactulose

Lactulose is a non-absorbed sugar-based laxative used to prevent and treat portal-systemic encephalopathy (brain effects of liver disease) and, in certain products, to treat constipation.

Brand names CholacConstilac SyrupConstuloseEnuloseGenerlac +6 more
Drug class Osmotic Laxative
Rx Forms 2
Dr. Brian Staiger, PharmD, BCPS
Reviewed by Last reviewed Jul 10, 2026 Content updated Oct 2, 2026
🧬 Where this information comes from Click to expand

The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 25 clinical label sets within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →

How we combine label and product data →
✓No current FDA shortage listed · checked Oct 4, 2026
Lactulose at a glance The quick version — the full detail is in the Patient Information Guide below.
Dr. Brian Staiger, PharmD, BCPS
The Pharmacist’s Take By · Clinical pharmacist · Written

Lactulose is a sugar the body barely absorbs, so gut bacteria turn it into acids in the colon that trap ammonia while its laxative effect flushes it out. On the market since the 1960s and available as a generic, it is the usual first choice for preventing and treating portal-systemic encephalopathy (confusion and drowsiness from ammonia buildup in liver disease), and some products treat constipation. Most people tolerate it well, though gas, bloating and cramps are common, especially early, and many find the taste very sweet. The one thing to watch is diarrhea that is severe or will not stop, since it can drain fluids, drop potassium and raise sodium.

Clinical pearls

  • For encephalopathy, the dose is adjusted to give two or three soft stools a day, so track them.
  • Avoid other laxatives, especially early in encephalopathy treatment, since extra loose stools can falsely suggest the lactulose dose is enough.
  • Tell your colonoscopy team you take lactulose, since its colon gas carries a theoretical explosion risk with electrocautery tools.
  • Mention lactulose before starting neomycin, other oral antibiotics or nonabsorbable antacids, which can blunt how it works in the colon.
How we write & review this content — our editorial policy →
How you get itPrescription only
Comes asOral solution, Enema
Earliest FDA record1966
Companies listing it with the FDA18
FDA label last updatedApr 14, 2026
FDA’s strongest warning (boxed)None on the label

Patient information guide — a plain-language walkthrough of Lactulose, written from its FDA label.

What Lactulose is used for

▾

Lactulose is used for two main purposes, depending on the product.

  • Prevention and treatment of portal-systemic encephalopathy, including hepatic pre-coma and coma (Generlac, Enulose and lactulose oral/rectal solutions).
  • Treatment of constipation (Constulose, Kristalose and lactulose for oral solution).

How Lactulose works

▾

Lactulose passes through to the colon nearly unchanged. Gut bacteria break it into acids that make the colon more acidic. This traps ammonia as ammonium so it is not absorbed, and the laxative effect clears it from the body.

Lactulose dosage

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  • Encephalopathy solutions (Generlac, Enulose, lactulose solution) are taken by mouth several times daily, adjusted to 2 or 3 soft stools a day. More frequent doses may be used at first.
  • Constipation products (Constulose, Kristalose, lactulose powder) are generally taken once daily and may take 24 to 48 hours to work.
  • Constulose may be mixed with fruit juice, water or milk. Powder is dissolved in water.

Follow your prescriber and label directions.

Dosing details from the FDA-approved label

From the Lactulose prescribing information (“Dosage and Administration”). Doses are set by your prescriber for your product, condition, kidney function and age — never change a dose on your own.

  • Adult, oral (portal-systemic encephalopathy)
    • 2 to 3 tablespoonfuls (30 to 45 mL, containing 20 g to 30 g of lactulose) three or four times daily
    • The dosage may be adjusted every day or two to produce 2 or 3 soft stools daily
    • Hourly doses of 30 to 45 mL may be used to induce rapid laxation in the initial phase of therapy
    • When the laxative effect has been achieved, the dose may be reduced to the recom
    • Improvement may occur within 24 hours but may not begin before 48 hours or even later.
  • Pediatric, infants (oral)
    • Recommended initial daily oral dose is 2.5 to 10 mL in divided doses
    • Goal is 2 to 3 soft stools daily
    • If the initial dose causes diarrhea, reduce the dose immediately; if diarrhea persists, discontinue. Very little information is available in young children.
  • Pediatric, older children and adolescents (oral)
    • Total daily dose is 40 to 90 mL
    • Goal is 2 to 3 soft stools daily
    • If the initial dose causes diarrhea, reduce the dose immediately; if diarrhea persists, discontinue.
  • Adult in impending coma or coma stage of portal-systemic encephalopathy (rectal retention enema)
    • Three hundred mL of lactulose solution mixed with 700 mL of water or physiologic saline, given as a retention enema via a rectal balloon catheter and retained for 30 to 60 minutes
    • May be repeated every 4 to 6 hours, or immediately if evacuated too promptly
    • Used when danger of aspiration exists or procedures interfere with oral dosing. Do not use cleansing enemas containing soapsuds or other alkaline agents. Start oral doses before the enema is stopped entirely.
  • Constulose solution, usual dose (oral)
    • 1 to 2 tablespoonfuls (15 to 30 mL, containing 10 g to 20 g of lactulose) daily
    • The dose may be increased to 60 mL daily if necessary
    • Maximum: 60 mL daily
    • Twenty-four to 48 hours may be required to produce a normal bowel movement; may be mixed with fruit juice, water or milk.
  • Adult, powder for solution (Lactulose, Kristalose)
    • 10 g to 20 g of lactulose daily
    • The dose may be increased to 40 g daily if necessary
    • Maximum: 40 g daily
    • Twenty-four to 48 hours may be required to produce a normal bowel movement.
Read the label’s full dosing text

DOSAGE AND ADMINISTRATION Oral Adult The usual adult oral dosage is 2 to 3 tablespoonfuls (30 to 45 mL, containing 20 g to 30 g of Generlac Solution) three or four times daily. The dosage may be adjusted every day or two to produce 2 or 3 soft stools daily. Hourly doses of 30 to 45 mL of Generlac Solution may be used to induce the rapid laxation indicated in the initial phase of the therapy of portal-systemic encephalopathy. When the laxative effect has been achieved, the dose of Generlac Solution may then be reduced to the recommended daily dose. Improvement in the patient's condition may occur within 24 hours but may not begin before 48 hours or even later. Continuous long-term therapy is indicated to lessen the severity and prevent the recurrence of portal-systemic encephalopathy. The dose of Generlac Solution for this purpose is the same as the recommended daily dose. Pediatric Very little information on the use of lactulose in young children and adolescents has been recorded. As with adults, the subjective goal in proper treatment is to produce 2 to 3 soft stools daily. On the basis of information available, the recommended initial daily oral dose in infants is 2.5 to 10 mL in divided doses. For older children and adolescents, the total daily dose is 40 to 90 mL. If the initial dose causes diarrhea, the dose should be reduced immediately. If diarrhea persists, Generlac Solution should be discontinued. Rectal When the adult patient is in the impending coma or coma stage of portal-systemic encephalopathy and the danger of aspiration exists, or when the necessary endoscopic or intubation procedures physically interfere with the administration of the recommended oral doses, Generlac Solution may be given as a retention enema via a rectal balloon catheter. Cleansing enemas containing soapsuds or other alkaline agents should not be used. Three hundred mL of Generlac Solution should be mixed with 700 mL of water or physiologic saline and retained for 30 to 60 minutes. Generlac Solution enema may be repeated every 4 to 6 hours. If the enema is inadvertently evacuated too promptly, it may be repeated immediately. The goal of treatment is reversal of the coma stage in order that the patient may be able to take oral medication. Reversal of coma may take place within 2 hours of the first enema in some patients.

Excerpted — the section continues on the label. Read the full Dosage and Administration section on DailyMed →

Lactulose side effects

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Common side effects

  • Gas (flatulence) and belching
  • Bloating (gaseous distention)
  • Abdominal cramps or discomfort
  • Diarrhea, especially with too much
  • Nausea
  • Vomiting

When to get medical help

  • Call your doctor if diarrhea is severe or does not stop, since it can cause loss of fluids and low potassium (hypokalemia) or high sodium (hypernatremia).
  • Call your doctor if you have ongoing vomiting.
  • Tell your doctor if you are not improving, or if your symptoms return or worsen.

Common effects are mostly digestive.

  • Gas and belching
  • Bloating
  • Abdominal cramps
  • Diarrhea with too much
  • Nausea and vomiting

Call your doctor for severe or persistent diarrhea, which can cause fluid loss and electrolyte problems.

Lactulose warnings and precautions

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  • Too much can cause diarrhea, fluid loss, low potassium and high sodium.
  • Theoretical explosion risk with electrocautery during proctoscopy or colonoscopy; thorough bowel cleansing with a non-fermentable solution is advised.

Lactulose interactions

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A few medicines can change how lactulose works.

  • Neomycin and other oral anti-infectives: may disrupt the bacteria needed to break down lactulose.
  • Nonabsorbable antacids: may blunt the drop in colon acidity.
  • Other laxatives: loose stools may falsely suggest the dose is enough.

Interactions listed in the FDA-approved label

From the Lactulose prescribing information (“Drug Interactions”): what the manufacturer studied or reported to the FDA.

  • Neomycin and other oral anti-infective agents: There have been conflicting reports; theoretically, elimination of certain colonic bacteria may interfere with the desired degradation of lactulose and prevent acidification of colonic contents. Closely monitor the status of the lactulose-treated patient during concomitant oral anti-infective therapy.
  • Nonabsorbable antacids: Preliminary studies in humans and rats suggest they may inhibit the desired lactulose-induced drop in colonic pH. Take a possible lack of desired effect into consideration before giving these drugs concomitantly with lactulose.
  • Other laxatives: Loose stools resulting from their use may falsely suggest that adequate lactulose dosage has been achieved. Other laxatives should not be used, especially during the initial phase of therapy for portal-systemic encephalopathy.
Read the label’s full interactions text

7 DRUG INTERACTIONS There have been conflicting reports about the concomitant use of neomycin and lactulose solution. Theoretically, the elimination of certain colonic bacteria by neomycin and possibly other anti-infective agents may interfere with the desired degradation of lactulose and thus prevent the acidification of colonic contents. Thus the status of the lactulose-treated patient should be closely monitored in the event of concomitant oral anti-infective therapy. Results of preliminary studies in humans and rats suggest that nonabsorbable antacids given concurrently with lactulose may inhibit the desired lactulose-induced drop in colonic pH. Therefore, a possible lack of desired effect of treatment should be taken into consideration before such drugs are given concomitantly with lactulose. Other laxatives should not be used, especially during the initial phase of therapy for portal-systemic encephalopathy, because the loose stools resulting from their use may falsely suggest that adequate lactulose dosage has been achieved.

Read the full Drug Interactions section on DailyMed →

Not a complete list. The label covers the interactions the manufacturer studied or reported, and our own interaction database does not cover every medicine either. Bring your full medication list, including vitamins and herbal products, to your pharmacist.

🌿17 supplements and herbs with documented Lactulose interactions, ranked by severity Check Lactulose against a supplement or herb →

Before taking Lactulose

▾
  • Kristalose is not for people needing a low galactose diet.
  • Pregnancy: use only if clearly needed.
  • Breastfeeding: use caution; unknown if it passes into milk.
  • Children: very little information is available.

Lactulose overdose

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No accidental overdoses have been reported. Diarrhea and abdominal cramps would be the expected main symptoms. The medication should be stopped.

What Lactulose does in the body

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Lactulose lowers blood ammonia and reduces the degree of portal-systemic encephalopathy. Controlled studies showed blood ammonia reductions of 25 to 50%, and clinical response in about 75% of patients. In chronic constipation, it increases the number of bowel movements per day and days with bowel movements.

How your body processes Lactulose

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Lactulose is poorly absorbed, and only small amounts reach the blood. Urinary excretion is 3% or less and is essentially complete within 24 hours. It reaches the colon essentially unchanged, where bacteria break it down into low molecular weight acids.

How to store Lactulose

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Store at controlled room temperature 15° to 30°C (59° to 86° F). Do not freeze. , a normal darkening of color may occur.

Written from the FDA-approved label with AI and reviewed by our pharmacy team. How we use AI →

17

Supplements & herbs that interact with Lactulose

17 supplements and herbal products have documented interactions with Lactulose in the licensed clinical database we use. Most are manageable — but your pharmacist should know about everything you take, including vitamins and herbals.

Severity mix
  • Major · 1
  • Moderate · 7
  • Minor · 9
ACTIVATED CHARCOAL Major COFFEE CHARCOAL Moderate EUROPEAN MANDRAKE Moderate GLUCOMANNAN Moderate GUAR GUM Moderate GUM ARABIC Moderate SLIPPERY ELM Moderate TRAGACANTH Moderate +9 more
Every supplement checked against Lactulose — ranked by severity The full interaction hub: 1 major · 7 moderate · 9 minor · every one linked to its full report. Check Lactulose against your exact supplements

Educational information from a licensed clinical database (Natural Medicines) — see our data sources & update cadence. Not medical advice: an interaction being documented does not mean it will happen to you; do not start or stop medications or supplements without professional guidance.

Lactulose: pharmacist answers to common questions

Quick, plain-English answers to the questions patients ask most about Lactulose — the kind of thing our pharmacy team would talk through with you at the counter.

What is lactulose for?

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It depends on the product. Some, like Generlac and Enulose, prevent and treat portal-systemic encephalopathy, a brain problem tied to liver disease. Others, like Constulose and Kristalose, treat constipation.

How soon will it work?

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For constipation, it can take 24 to 48 hours to produce a bowel movement. For encephalopathy, you may improve within 24 hours, but it might not start before 48 hours or later.

What side effects should I expect?

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Gas, bloating, belching and cramps are the most common, affecting about 20% of people. Nausea and vomiting can happen. If you get diarrhea, tell your doctor, since the dose may need lowering.

Can I take other laxatives or antacids with it?

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Check with me or your doctor first. Other laxatives can mask whether your lactulose dose is working, and nonabsorbable antacids may weaken its effect. Neomycin and similar antibiotics can also interfere.

Is it safe in pregnancy or while breastfeeding?

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Animal studies showed no harm, but there are no good studies in pregnant women, so it should be used only if clearly needed. It's unknown whether it passes into breast milk, so talk to your doctor.

Do I need to tell anyone before a colonoscopy?

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Yes. Tell your care team you take lactulose. There's a theoretical gas explosion risk with electrocautery, so a thorough bowel cleansing with a non-fermentable solution is advised.

Is Lactulose available over the counter?

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No. Lactulose is a prescription medicine: every Lactulose product listed with the FDA is prescription only, so it is not sold over the counter. Your prescriber decides whether it is appropriate for you, and your pharmacist dispenses it.

When was Lactulose first available?

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The earliest FDA record we hold for Lactulose is from 1966: its first approval in Drugs@FDA or its earliest product listing in the NDC Directory, whichever is older. Many older medicines were in use before their first formal FDA approval, so this is the earliest date on record, not necessarily when Lactulose was first used.

Who makes Lactulose?

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18 companies currently list Lactulose products in the FDA's NDC Directory, including PAI Holdings, LLC dba PAI Pharma, Chartwell RX, LLC, Apozeal Pharmaceuticals Inc. That count includes repackagers and distributors as well as manufacturers (companies that sell only the raw ingredient are not counted), so fewer companies actually make it; the label on your bottle names the one that supplied yours.

Answers drafted from the FDA-approved label with AI and reviewed by our pharmacy team. How we use AI →

More about Lactulose on HelloPharmacist

📊Lactulose supplement interactions17 checked — ranked by severity 🌿Drug & Supplement CheckerLactulose vs. vitamins & herbs 💬Ask a PharmacistFree answer, usually < 24h 🔎NDC & pricing lookupFind Lactulose NDCs & costs 🅰️Browse Drugs A–ZLook up any medication
Detailed data & references for Lactulose Forms & strengths, pricing, billing codes, manufacturers, safety reports and sourcing — the data behind the page. Most people can stop here. Each section below opens on a tap.

Lactulose forms and strengths (how it comes)

Lactulose is available in 2 forms. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.

Oral solution

By mouth
Brands Constulose Kristalose
How this form is used
What it may be used for
  • Constulose is labeled for the treatment of constipation.
  • Kristalose (for oral solution) is labeled for the treatment of constipation.
  • Lactulose for oral solution (powder) is labeled for the treatment of constipation.
Important instructions
  • Constulose is generally taken once daily and may be mixed with fruit juice, water or milk.
  • Kristalose and lactulose powder are generally taken once daily, and may take 24 to 48 hours to produce a bowel movement.
  • Lactulose powder packets are dissolved in about half a glass (4 ounces) of water.
Available strengths 6 strengths
10 g/10 g 10 g/15 mL 20 g/20 g 20 g/30 mL 1 kg/kg 1000 kg/1000 kg
54 FDA-listed product records ⓘ

Enema

By mouth · Rectal
Brands Enulose Generlac
How this form is used
What it may be used for
  • Enulose and Generlac are labeled for preventing and treating portal-systemic encephalopathy, including hepatic pre-coma and coma.
  • Lactulose oral/rectal solution is labeled for portal-systemic encephalopathy.
Important instructions
  • Enulose and Generlac oral solution is taken several times daily and adjusted to produce 2 or 3 soft stools daily.
  • Enulose and Generlac may be given more often at the start of therapy to produce rapid laxation, then reduced.
  • Enulose and Generlac long-term therapy is used to lessen severity and prevent recurrence.
Available strengths 1 strength
10 g/15 mL
7 FDA-listed product records ⓘ

Lactulose on the U.S. market: products, makers and brands

How Lactulose appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.

18 companies list 33 Lactulose product records with the FDA, mostly as oral solution, enema; the earliest marketing or approval year on record is 1966. Brand names on the directory include Cholac, Constilac Syrup, Constulose and 8 more; the rest are generics.

2
Dose forms ⓘ
18
Labelers (makers, repackagers, distributors)
6
Brand names
33
FDA-listed product records ⓘ
1966
Earliest FDA record ⓘ

FDA-listed product records by dose form (tablet variants merged) — FDA National Drug Code Directory. Record counts are not sales or prescription volume.

Also listed with the FDA, not a patient dose form: Powder (3) — bulk drug substance sold to compounders/manufacturers and multi-item kits. These aren’t counted in the dose-form total above.

PAI Holdings, LLC dba PAI Pharma18%
Chartwell RX, LLC12%
Apozeal Pharmaceuticals Inc6%
Actavis Pharma, Inc.6%
Chartwell Governmental & Specialty RX, LLC.6%
Cumberland Assured Products Inc.6%
Other makers45%

Share of FDA-listed product records by manufacturer — FDA National Drug Code Directory. Record counts are not sales or prescription volume.

How widely Lactulose is used (Medicaid data)

A general measure of how commonly Lactulose is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q1–Q4 2025, summed across every form and brand of the drug.

Think of this as a proxy for how widely Lactulose is used, drawn from freely available public data. Medicaid is just one program — these numbers don’t include Medicare, other government coverage, or commercial and cash-pay prescriptions, so real-world use is higher than what’s shown here.

835,520
Medicaid prescriptions filled (Q1–Q4 2025)
$31.1M gross Medicaid reimbursement (before mandatory rebates — net cost is lower)

How commonly is Lactulose prescribed? Of the 1,601 medications we measure, Lactulose ranks #196 by Medicaid prescriptions — more than 88% of them.

Where Lactulose ranks among the drugs we measure · Q1–Q4 2025 · neighbors ±5
Total prescriptions — #196 of 1,601
#191 Ceftriaxone Injection 875,273 Rx #192 Tacrolimus 862,723 Rx #193 Cyproheptadine 854,560 Rx #194 Meclizine 846,276 Rx #195 Erythromycin Ophthalmi... 841,932 Rx #196 Lactulose 835,520 Rx #197 Haloperidol 821,226 Rx #198 Calcium Chloride / Pot... 809,101 Rx #199 Hydralazine 805,117 Rx #200 Valsartan and Sacubitr... 792,623 Rx #201 Medroxyprogesterone In... 789,786 Rx

Utilization by Lactulose product

Pick a product to see its own Medicaid numbers. Each chip is one clinical product — a specific strength & dosage form as defined by RxNorm — with brand-name and generic versions combined.

The 667 mg/mL oral solution is the most-dispensed Lactulose product — about 96% of these Medicaid prescriptions.

lactulose 667 MG/ML Oral Solution Most dispensed

800,305 Medicaid prescriptions (Q1–Q4 2025) 96% of Lactulose prescriptions shown $17.4M gross reimbursement (before rebates) ≈ $22 per prescription (gross)

Summed across the 23 of 104 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 391937

lactulose 10000 MG Powder for Oral Solution

19,738 Medicaid prescriptions (Q1–Q4 2025) 2% of Lactulose prescriptions shown $5.7M gross reimbursement (before rebates) ≈ $288 per prescription (gross)

Summed across the 3 of 9 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 1251190

lactulose 20000 MG Powder for Oral Solution

15,477 Medicaid prescriptions (Q1–Q4 2025) 2% of Lactulose prescriptions shown $8M gross reimbursement (before rebates) ≈ $519 per prescription (gross)

Summed across the 3 of 10 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 1251194

Shares are of the Medicaid prescriptions shown here. Product grouping follows RxNorm (the National Library of Medicine’s drug terminology), so “one product” means one strength & dosage form regardless of manufacturer. Dollar figures are gross Medicaid reimbursement before mandatory rebates — rebates (often large, especially for brand-name drugs) are confidential, so actual net cost to Medicaid is lower than shown.

Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Lactulose, and across all states and both fee-for-service and managed-care claims. A general popularity signal; it excludes Medicare, commercial insurance and cash prescriptions, so it is not total U.S. use. Based on the 29 of 123 listed Lactulose NDCs with Medicaid activity.

Compare Lactulose products

A representative set of FDA-listed product records for Lactulose — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)

Showing 33 of 33 products — FDA National Drug Code Directory. See every product, package size and price: browse all 33 Lactulose NDCs →

Lactulose recall history

A recall is when a specific batch of a medicine is pulled from the market — usually a manufacturing issue, not a problem with the drug itself. Class I is most serious, Class III least.

The FDA’s enforcement reports list no Lactulose recalls since July 2021.

✅No Lactulose recalls on record since July 2021

Source: FDA enforcement (recall) reports, via openFDA; our copy was last updated Sep 24, 2026.

RxNorm Concept Web — From Ingredient to Every Form and Strength

This page starts with one ingredient concept (IN). The branches below show its dose-form concepts (SCDF), then the available clinical drug and strength concepts (SCD). Combination products remain separate concepts with their own pages.

Ingredient (IN) Lactulose RxCUI 6218 2 dose forms · 4 strengths
  1. Dose form (SCDF) Oral Solution RxCUI 378092 In current FDA listings
    Clinical drug / strength (SCD) 667 MG/ML RxCUI 391937 670 MG/ML RxCUI 104148
  2. Dose form (SCDF) Powder for Oral Solution RxCUI 1868570 In current FDA listings
    Clinical drug / strength (SCD) 10000 MG RxCUI 1251190 20000 MG RxCUI 1251194

Look up RxCUI 6218 in the RxCUI Atlas →

RxNorm is the U.S. National Library of Medicine’s normalized drug vocabulary. Its concept hierarchy can include forms that are not currently marketed; the status on each branch compares that concept with current FDA listings. RxCUIs identify vocabulary concepts, not individual packages or manufacturers.

Lactulose brand names

Lactulose is sold under 11 brand names in the FDA directory — Cholac, Constilac Syrup, Constulose, Enulose and others. A brand and its generic contain the same active ingredient; the brand name belongs to one company's product.

Cholac Constilac Syrup Constulose Enulose Generlac Evalose Syrup Heptalac Kristalose Laxilose Portalac LACTULOSE Crystalline

Who makes Lactulose: manufacturers and labelers

18 companies list Lactulose products with the FDA. By number of product records, the largest are PAI Holdings, LLC dba PAI Pharma, Chartwell RX, LLC, Apozeal Pharmaceuticals Inc. Labelers include manufacturers and repackagers; the product in your bottle depends on which one your pharmacy stocks.

PAI Holdings, LLC dba PAI Pharma 6 Chartwell RX, LLC 4 Apozeal Pharmaceuticals Inc 2 Actavis Pharma, Inc. 2 Chartwell Governmental & Specialty RX, LLC. 2 Cumberland Assured Products Inc. 2 Cumberland Pharmaceuticals Inc. 2 Foxland Pharmaceuticals, Inc. 2 Trifluent Pharma, Inc. 2 American Health Packaging 1 Atlantic Biologicals Corp. 1 Bryant Ranch Prepack 1 Cardinal Health 107, LLC 1 Fresenius Kabi Austria GmbH 1 Lannett Company, Inc. 1 Proficient Rx LP 1 Sun Pharmaceutical Industries, Inc. 1 Xttrium Laboratories, Inc. 1

Lactulose drug class (RxNorm)

Lactulose belongs to the Osmotic Laxative class.

Pharmacologic class Osmotic Laxative
Drug family (ATC) Osmotically acting laxatives
How it works Osmotic Activity, Acidifying Activity

Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.

Sources for this Lactulose page

Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.

📄
FDA-filed drug labels (SPL) Uses, dosing, warnings & side effects from SPL records retrieved through openFDA; the linked representative set can be verified on DailyMed. ✓ Linked label effective Apr 14, 2026
🏭
Forms, brands & labelersAggregated from ingredient-matched FDA National Drug Code Directory product records for Lactulose.
📈
Real-world reportsThe FDA Adverse Event Reporting System (FAERS), served through openFDA.
🚨
Recalls & shortagesopenFDA drug-enforcement reports and the FDA drug-shortage database.
🧾 Clinical label set — FDA-filed SPL labels retained for Lactulose after exact ingredient or ingredient-combination matching and applicable route/form matching
Clinical labels in scope
25
Finished products in the current FDA directory
33
Companies listing them (makers, repackagers, distributors)
18
FDA labeler codes behind them ⓘ
18
Linked representative label ⓘ
Xttrium Laboratories, Inc.
Linked label effective
Apr 14, 2026
Composite sections available
17
Linked SPL Set ID
df62ad54-5aba-4d05-e053-2a95a90aa48d
Linked SPL Document ID
4f6f0368-4b59-a9df-e063-6294a90ae43c
Open the linked representative label on DailyMed ↗

How this page is built

HelloPharmacist combines public FDA and NLM records and does not author the underlying clinical facts. The plain-language sections are written with AI from the FDA-approved label text and reviewed by our pharmacy team before publication. Xttrium Laboratories, Inc. is the representative DailyMed label linked for verification and dates. This is general education, not medical advice: always talk to your doctor or pharmacist about your own medicines. How we build and review drug pages →