Generlac (Lactulose) - Indications and Dosage

INDICATIONS AND USAGE

For the prevention and treatment of portal-systemic encephalopathy, including the stages of hepatic pre-coma and coma.

Controlled studies have shown that lactulose therapy reduces the blood ammonia levels by 25–50%; 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 solution therapy. In the treatment of chronic portal-systemic encephalopathy, lactulose solution has been given for over 2 years in controlled studies.

DOSAGE AND ADMINISTRATION

Oral

Adult

The usual adult oral dosage is 30 to 45 mL (2 to 3 tablespoonfuls, 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 pediatric patients 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 pediatric patients, 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. Generlac Solution, given orally in the recommended doses, should be started before Generlac Solution by enema is stopped entirely.

HOW SUPPLIED

Generlac Solution (Lactulose Solution, USP) is a colorless to yellow, unflavored solution containing 10 g of lactulose/15 mL (667 mg lactulose/mL). It is available in the following container sizes:

1 Pint (473 mL) bottles
2 Quart (1892 mL) bottles