lactulose (redirected from Constulose)

lactulose /lac·tu·lose/ (lak´tu-lōs) a synthetic disaccharide used as a laxative and to enhance excretion or formation of ammonia in the treatment of hepatic encephalopathy.

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lactulose

[lak′tyəlōs]

a nonabsorbable synthetic disaccharide, 4-0-beta-d-galactopyranosyl-D-fructose, C₁₂H₂₂O₁₁. It is hydrolyzed in the colon by bacteria primarily to lactic acid and small amounts of formic and acetic acids, which results in increased osmotic pressure and acidification of the colonic contents. It is used as a cathartic in chronic constipation. Because the acidification causes ammonia to be removed from the blood to form ammonium ion, it is also used in the treatment of hepatic coma. Its ability to increase fecal water content, however, may also cause diarrhea.

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lactulose

a synthetic disaccharide used as a cathartic and to enhance the excretion of ammonia in the treatment of hepatic encephalopathy.

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lactulose

Apo-Lactulose (CA), Constulose, Duphalac (UK), Enulose, Euro-Lac (CA), Generlac, Gen-Lac (CA), Kristalose, Lactugal (UK), Lactulax (CA), Lemlax (UK), Regulose (UK), PMS-Lactulose (CA), Ratio-Lactulose (CA)

Pharmacologic class: Osmotic

Therapeutic class: Laxative

Pregnancy risk category B

Action

Produces osmotic effect, which increases water content in colon and enhances peristalsis. Breakdown products in colon lead to acidification of colonic contents, softening of feces, and decreased ammonia absorption from colon to systemic circulation. These effects reduce blood ammonia level in portal-system encephalopathy.

Availability

Powder (single-use packets): 10 g, 20 g

Syrup: 10 g/15 ml

⊘Indications and dosages

➣ Constipation

Adults: 10 to 20 g (15 to 30 ml) P.O. daily; may increase to 60 ml daily p.r.n.

➣ Portal-system encephalopathy

Adults: 20 to 30 g (30 to 45 ml) P.O. three or four times daily until two or three soft stools are produced daily. Therapy may continue long term.

Contraindications

• Patients requiring low-galactose diet

Precautions

Use cautiously in:
• diabetes mellitus
• elderly patients
• pregnant or breastfeeding patients
• children.

Administration

• Don't give concurrently with other laxatives.
• Dissolve contents of single-use packet in 4 oz of water or juice.
• Dilute syrup with water or fruit juice to mask taste.

Route	Onset	Peak	Duration
P.O.	24-48 hr	Unknown	Unknown

Adverse reactions

GI: diarrhea, intestinal cramps, abdominal distention, flatulence

Metabolic: hyperglycemia (in diabetic patients)

Interactions

Drug-drug. Anti-infectives: decreased lactulose efficacy

Other laxatives: interference with response to lactulose (in patients with hepatic encephalopathy)

Drug-diagnostic tests. Blood ammonia: 25% to 50% decrease

Glucose: increased level (in diabetic patients)

Patient monitoring

• Watch for adverse GI reactions.
• Check stool consistency and frequency.
• Monitor electrolyte levels, especially in elderly patients.
• Check blood glucose level in diabetic patients.

Patient teaching

• Instruct patient to dissolve contents of single-use packet in 4 oz of water or juice.
• Suggest that patient dilute syrup with water or juice to mask taste.
• Tell patient drug may cause flatulence and intestinal cramps at first, but these symptoms usually subside.
• Inform patient that excessive use may cause diarrhea and excessive fluid loss.
• Encourage patient to drink adequate fluids and to report signs and symptoms of dehydration.
• As appropriate, review all other significant adverse reactions and interactions, especially those related to the drugs and tests mentioned above.