What is Lactulose used for?

Lactulose is indicated for: blood ammonia absorption, Constipation, Hepatic disease, hepatic disorders, Hepatic encephalopathy, Hepatic encephalopathy (reduces blood ammonia), Hepatic lipidosis, hyperammonemia.

Which species have cited Lactulose dosing data?

Lactulose dosing in the ExoticRx formulary covers 21 species: African Grey Parrot, African Pygmy Hedgehog, Bearded Dragon, Blue-and-Gold Macaw, Blue-tongue Skink, Cat (Domestic), Chinchilla, Crested Gecko, Degu, Dog (Domestic), Dwarf Hamster, Ferret, Guinea Pig, Leopard Gecko, Lovebird, Pet Rat, Red-eared Slider, Russian Tortoise, Sulcata Tortoise, Umbrella Cockatoo, Veiled Chameleon.

Is Lactulose a controlled substance?

Lactulose is not federally scheduled in the US. Controlled-drug status differs by country — verify your local rules.

Lactulose

US brand names:Kristalose, Cephulac

Calculate dosage

Sourced from published veterinary references. Awaiting credentialed clinical reviewer — our editorial process.

Lactulose is dosed at 0.5 ml/kg PO q12h in guinea pigs, per Meredith A. BSAVA Small Animal Formulary: Part B: Exotic Pets, British Small Animal Veterinary Association, Quedgeley, Gloucester, UK; 2015. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.801 — Carpenter's Exotic Animal Formulary 6th ed, Table 9.7 (Miscellaneous Agents Used in Rodents). Verify against current literature before clinical use.

Drug Class

Gastrointestinal

Routes

PORECTAL

Indications

blood ammonia absorptionConstipationHepatic diseasehepatic disorders

Mechanism of Action

Synthetic disaccharide broken down by colonic bacteria to lactic, acetic, and formic acids. Osmotic effect draws water into colon. Acidifies colonic contents, converting ammonia to non-absorbable ammonium.

Side effects & warnings

Dose to effect (soft stool). Excessive doses cause diarrhea, flatulence, cramping. Monitor electrolytes with chronic use. Essential in hepatic encephalopathy management.

Evidence levels across 22 dose rules

Weak×15Moderate×6Strong×1

Each ExoticRx dose rule is graded by the strength of its primary evidence — see the editorial process.

Sample dosing (2 of 22 cited rules)

A dog/cat sample is shown here. Cited dosing for all 21 species — reptiles, birds, pocket pets, livestock, and equine — is free on the per-species pages above. Pro adds the weight-based calculator for every species.

Species	Route	Dose	Frequency	Evidence	Source
Cat (Domestic)	PO	0.5–1 ml/kg	q8-12h	Strong	Plumb's Veterinary Drug Handbook, 10th ed (2023) — Plumb's 10th ed printed p.735, Lactulose monograph.Compilation only — we have not located an independent source that prints this figure.
Dog (Domestic)	PO	0.5–1 ml/kg	q8-12h	Weak	BSAVA Small Animal Formulary, 10th Ed, Part A — Canine and Feline: Lactulose, printed p.222Compilation only — we have not located an independent source that prints this figure.

Backed by 17 published sourcesShow

· 122. Meredith A. BSAVA Small Animal Formulary: Part B: Exotic Pets, British Small Animal Veterinary Association, Quedgeley, Gloucester, UK; 2015. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.801 — Carpenter's Exotic Animal Formulary 6th ed, Table 9.7 (Miscellaneous Agents Used in Rodents).
· 149. Jepson L. Lizards. Exotic Animal Medicine: A Quick Reference Guide. Philadelphia: Saunders/Elsevier; 2009:268-314. | 150. Jepson L. Snakes. Exotic Animal Medicine: A Quick Reference Guide. Philadelphia: Saunders/Elsevier; 2009:315-357. | 151 not cited here; 314. Stahl SJ. Captive management, breeding, and common medical problems of the veiled chameleon (Chamaeleo calyptratus). Proc Annu Conf Assoc Rept Amph Vet. 1997;29-40. — Source: Mader's Reptile and Amphibian Medicine and Surgery, 3rd Ed, p.1420
· 149. Jepson L. Lizards. Exotic Animal Medicine: A Quick Reference Guide. Philadelphia: Saunders/Elsevier; 2009:268-314. — Source: Mader's Reptile and Amphibian Medicine and Surgery, 3rd Ed, p.1420

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222. Jepson L. Turtles and tortoises. In: Exotic Animal Medicine: A Quick Reference Guide, Saunders/Elsevier, Philadelphia, PA; 2009:358-411. | 243. Klaphake E, Gibbons PM, Sladky KK, et al. Reptiles. In: Carpenter JW, eds. Exotic Animal Formulary, 5th ed., Elsevier, St. Louis, MO; 2018:81-166. | 442. Stahl SJ. Medical management of bearded dragons. Proc North Am Vet Conf; 1999:789-792. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.274 — Carpenter's Exotic Animal Formulary 6th ed, Table 4.11 (Miscellaneous Agents Used in Reptiles).

· 222. Jepson L. Turtles and tortoises. In: Exotic Animal Medicine: A Quick Reference Guide, Saunders/Elsevier, Philadelphia, PA; 2009:358-411. || 243. Klaphake E, Gibbons PM, Sladky KK, et al. Reptiles. In: Carpenter JW, eds. Exotic Animal Formulary, 5th ed., Elsevier, St. Louis, MO; 2018:81-166. || 442. Stahl SJ. Medical management of bearded dragons. Proc North Am Vet Conf; 1999:789-792. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.274 — Carpenter's Exotic Animal Formulary 6th ed, Table 4.11 (Miscellaneous Agents Used in Reptiles).

· 30. Jepson L. Hedgehogs. In: Jepson L, eds. Exotic Animal Medicine: A Quick Reference Guide, 2nd ed., Elsevier, St. Louis, MO; 2016:198-230. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.745 — Carpenter's Exotic Animal Formulary 6th ed, Table 8.7 (Miscellaneous Agents Used in Hedgehogs).

· 43. Bailey TA, Apo MM. Pharmaceutics commonly used in avian medicine. In: Samour J, eds. Avian Medicine, 3rd ed., Mosby Elsevier, Edinburgh, Scotland; 2016:637-678. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.492 doi:10.1016/b978-0-7234-3832-8.00023-7 — Carpenter's Exotic Animal Formulary 6th ed, Table 5.18 (Miscellaneous Agents Used in Birds).

· 43. Bailey TA, Apo MM. Pharmaceutics commonly used in avian medicine. In: Samour J, eds. Avian Medicine, 3rd ed., Mosby Elsevier, Edinburgh, Scotland; 2016:637-678. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.492 — Carpenter's Exotic Animal Formulary 6th ed, Table 5.18 (Miscellaneous Agents Used in Birds).

· 442. Stahl SJ. Medical management of bearded dragons. Proc North Am Vet Conf; 1999:789-792. / 222. Jepson L. Turtles and tortoises. In: Exotic Animal Medicine: A Quick Reference Guide, Saunders/Elsevier, Philadelphia, PA; 2009:358-411. / 243. Klaphake E, Gibbons PM, Sladky KK, et al. Reptiles. In: Carpenter JW, eds. Exotic Animal Formulary, 5th ed., Elsevier, St. Louis, MO; 2018:81-166. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.274 — Carpenter's Exotic Animal Formulary 6th ed, Table 4.11 (Miscellaneous Agents Used in Reptiles).

· 45. Lightfoot T. Therapeutics of African pygmy hedgehogs and prairie dogs. Vet Clin North Am Exot Anim Pract. 2000;3:155-172. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.745 — Carpenter's Exotic Animal Formulary 6th ed, Table 8.7 (Miscellaneous Agents Used in Hedgehogs).

· Bailey TA, Apo MM. Pharmaceutics commonly used in avian medicine. In: Samour J, eds. Avian Medicine, 3rd ed., Mosby Elsevier, Edinburgh, Scotland; 2016:637-678. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.492 — Carpenter's Exotic Animal Formulary 6th ed, Table 5.18 (Miscellaneous Agents Used in Birds).

· Hedley J. Small Animal Formulary-Part B: Exotic Pets, 10th ed., British Small Animal Veterinary Association, Gloucester, UK; 2020. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.956 — Carpenter's Exotic Animal Formulary 6th ed, Table 11.10 (Miscellaneous Agents Used in Ferrets.a).

· Jepson L. Turtles and tortoises. In: Exotic Animal Medicine: A Quick Reference Guide, Saunders/Elsevier, Philadelphia, PA; 2009:358-411. | Klaphake E, Gibbons PM, Sladky KK, et al. Reptiles. In: Carpenter JW, eds. Exotic Animal Formulary, 5th ed., Elsevier, St. Louis, MO; 2018:81-166. | Stahl SJ. Medical management of bearded dragons. Proc North Am Vet Conf; 1999:789-792. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.274 — Carpenter's Exotic Animal Formulary 6th ed, Table 4.11 (Miscellaneous Agents Used in Reptiles).

· Jepson L. Turtles and tortoises. In: Exotic Animal Medicine: A Quick Reference Guide, Saunders/Elsevier, Philadelphia, PA; 2009:358-411. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.274 — Carpenter's Exotic Animal Formulary 6th ed, Table 4.11 (Miscellaneous Agents Used in Reptiles).

· Meredith A. BSAVA Small Animal Formulary: Part B: Exotic Pets, British Small Animal Veterinary Association, Quedgeley, Gloucester, UK; 2015. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.801 — Carpenter's Exotic Animal Formulary 6th ed, Table 9.7 (Miscellaneous Agents Used in Rodents).