Lactulose Shortage: What Providers and Prescribers Need to Know in 2026

Lactulose is not in a declared national shortage as of 2026, but patients — particularly those on Kristalose powder or rectal formulations — may still report difficulty accessing their medication. This guide covers the clinical landscape, formulation considerations, appropriate therapeutic alternatives, and practical approaches to help patients maintain uninterrupted treatment.

Current Availability Status

Generic lactulose oral solution (10 g/15 mL) is not listed on the FDA Drug Shortage Database as of 2026 and is produced by multiple manufacturers, providing supply redundancy. With approximately 900,000 prescriptions filled in 2023, it remains one of the most widely dispensed laxative agents in the United States. However, providers should be aware of important distinctions across formulations:

• Generic lactulose solution: Widely available at most retail and hospital pharmacies. Multiple manufacturers supply this formulation.
• Kristalose (crystalline lactulose powder): Single-source (Cumberland Pharmaceuticals). No generic equivalent. May have intermittent availability at retail pharmacies. Consider switching patients to lactulose solution if access issues arise (10 g powder = 15 mL solution).
• Rectal lactulose formulation: Primarily compounded or supplied through hospital/specialty pharmacies. Not routinely stocked at retail pharmacies. For outpatient hepatic encephalopathy management, oral therapy should be the primary route.

Clinical Indications and Dosing Reference

Chronic constipation: 15–30 mL (10–20 g) orally once daily; may increase to 60 mL/day. Onset 24–48 hours.

Hepatic encephalopathy (prevention/treatment): 30–45 mL (20–30 g) orally 3–4 times daily, titrated to produce 2–3 soft bowel movements per day. In acute presentation, 20–30 g may be given hourly until catharsis is achieved, then reduced to maintenance dosing.

Rectal (acute HE): 300 mL (200 g) in 700 mL water or normal saline, retained for 30–60 minutes every 4–6 hours. Transition to oral therapy before discontinuing rectal administration.

Therapeutic Alternatives by Indication

For Chronic Constipation:

• Polyethylene glycol 3350 (PEG/MiraLax): OTC osmotic laxative; favored by ACG guidelines for chronic constipation; superior tolerability profile (less flatulence); 17 g daily.
• Senna: Stimulant laxative; faster onset; appropriate for short-term or opioid-induced constipation.
• Lubiprostone (Amitiza): Chloride channel activator; Rx; appropriate for chronic idiopathic constipation or OIC refractory to OTC agents.
• Linaclotide (Linzess): Guanylate cyclase-C agonist; Rx; indicated for CIC and IBS-C.

For Hepatic Encephalopathy:

• Rifaximin (Xifaxan) 550 mg BID: Non-absorbable antibiotic that reduces ammonia-producing gut flora. AASLD/EASL guidelines support rifaximin as a complement to lactulose for secondary HE prevention, or as an alternative when lactulose is not tolerated. Significant cost concern; requires PA for most plans.
• Polyethylene glycol (for acute HE): The HELP trial (JAMA Internal Medicine) demonstrated PEG led to more rapid HE resolution than lactulose at 24 hours (91% vs 52% improvement in HESA score). Consider PEG as an alternative for hospitalized patients with acute overt HE.
• Lactitol: Similar mechanism to lactulose; used in European guidelines; limited availability in the US market.

Key Contraindications and Precautions to Document

• Galactosemia: Absolute contraindication. Lactulose solution contains less than 1.6 g galactose per 15 mL.
• Diabetes: Use with caution; lactulose contains small amounts of galactose and lactose that may affect glucose levels.
• Electrocautery procedures: Lactulose produces hydrogen gas in the colon. Patients undergoing electrocautery (colonoscopy, proctoscopy) should use a non-fermentable bowel prep solution instead.
• Long-term use monitoring: Monitor serum electrolytes in patients on lactulose for more than 6 months or in elderly/renally impaired patients; excessive dosing can cause hypokalemia and hypernatremia.

How to Help Patients Access Lactulose

When patients report difficulty filling their prescription, providers can help by:

1. Authorizing a formulation switch (e.g., Kristalose → generic solution) with explicit dosing equivalence.
2. Prescribing a 90-day supply to enable mail-order dispensing.
3. Directing patients to medfinder.com/providers — a service that calls area pharmacies to identify which ones have the medication in stock.
4. For Kristalose patients: directing them to the Cumberland Pharmaceuticals manufacturer coupon (as low as $5/30-day supply via kristalose.com or 1-855-584-6194).

Learn more about how medfinder helps providers get their patients' prescriptions filled quickly.