Lactulose

For the prevention and treatment of portal-systemic encephalopathy, including the stages of hepatic pre-coma and coma. Controlled studies have shown that lactulose solution therapy reduces the blood ammonia levels by 25 to 50%; this is generally paralleled by an improvement in the patients' mental state and by an improvement in EEG patterns. The clinical response has been observed in about 75% of patients, which is at least as satisfactory as that resulting from neomycin therapy. An increase in patients' protein tolerance is also frequently observed with lactulose therapy. …

• Oral Adult: The usual adult, oral dosage is 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 of Lactulose 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 lactulose 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 lactulose 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, lactulose should be discontinued. …

• Very little information on the use of lactulose
• In pediatric patients has been recorded (see DOSAGE AND ADMINISTRATION )

Since lactulose solution contains galactose (less than 1.6 g/15 mL), it is contraindicated in patients who require a low galactose diet.

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. …

A theoretical hazard may exist for patients being treated with lactulose solution who may be required to undergo electrocautery procedures during proctoscopy or colonoscopy. Accumulation of H 2 gas in significant concentration in the presence of an electrical spark may result in an explosive reaction. Although this complication has not been reported with lactulose, patients on lactulose therapy undergoing such procedures should have a thorough bowel cleansing with a non-fermentable solution. Insufflation of CO 2 as an additional safeguard may be pursued but is considered to be a redundant measure.

Precise frequency data are not available. Lactulose may produce gaseous distention with flatulence or belching and abdominal discomfort such as cramping in about 20% of patients. Excessive dosage can lead to diarrhea with potential complications such as loss of fluids, hypokalemia, and hypernatremia. Nausea and vomiting have been reported. To report SUSPECTED ADVERSE EVENTS, contact the FDA at 1-800-FDA-1088 or http://www.fda.gov/ for voluntary reporting of adverse reactions.

Pregnancy Teratogenic Effects Pregnancy category B . Reproduction studies have been performed in mice, rats, and rabbits at doses up to 2 or 4 times the usual human oral dose and have revealed no evidence of impaired fertility or harm to the fetus due to lactulose. There are, however, no adequate and well-controlled studies in pregnant women. …

Signs and Symptoms There have been no reports of accidental overdosage. In the event of overdosage, it is expected that diarrhea and abdominal cramps would be the major symptoms. Medication should be terminated. Oral LD 50 : The acute oral LD 50 of the drug is 48.8 mL/kg in mice and greater than 30 mL/kg in rats. Dialysis: Dialysis data are not available for lactulose. Its molecular similarity to sucrose, however, would suggest that it should be dialyzable.

Take it when you remember, unless it is nearly time for the next dose. Then skip the missed one. Never take two doses at once to make up for it. Check your leaflet, as some medicines are different.