Lactulose

DRUG INFORMATION

  ADULT
    - DOSAGE & ADMINISTRATION 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.
      Source: US FDA label for lactulose (Lactulose), section 'dosage and
      administration', retrieved 2026-08-29
    - 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.
      Source: US FDA label for lactulose (Lactulose), section 'dosage and
      administration', retrieved 2026-08-29
    - DOSAGE & ADMINISTRATION 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.
      Source: US FDA label for lactulose (Lactulose), section 'dosage and
      administration', retrieved 2026-08-29

  CHILD
    - Very little information on the use of lactulose in pediatric patients has been
      recorded. (See DOSAGE AND ADMINISTRATION.)
      Source: US FDA label for lactulose (Lactulose), section 'pediatric use', retrieved
      2026-08-29
    - DOSAGE & ADMINISTRATION 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.
      Source: US FDA label for lactulose (Lactulose), section 'dosage and
      administration', retrieved 2026-08-29
    - On the basis of information available, the recommended initial daily oral dose in
      infants is 2.5 to 10 mL in divided doses.
      Source: US FDA label for lactulose (Lactulose), section 'dosage and
      administration', retrieved 2026-08-29

  RENAL IMPAIRMENT
    - No kidney-impairment dose in this label. Not a statement that none is needed.
      Source: Read and found silent: the US FDA label for lactulose (Lactulose),
      retrieved 2026-08-29

  HEPATIC IMPAIRMENT
    - No liver-impairment dose in this label. Not a statement that none is needed.
      Source: Read and found silent: the US FDA label for lactulose (Lactulose),
      retrieved 2026-08-29

  PREGNANCY
    - Teratogenic Effects Pregnancy category B .
      Source: US FDA label for lactulose (Lactulose), section 'pregnancy', retrieved
      2026-08-29
    - 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.
      Source: US FDA label for lactulose (Lactulose), section 'pregnancy', retrieved
      2026-08-29
    - There are, however, no adequate and well-controlled studies in pregnant women.
      Source: US FDA label for lactulose (Lactulose), section 'pregnancy', retrieved
      2026-08-29

  BREASTFEEDING   [ CAUTION ]
    The label allows it only when the benefit is judged to outweigh the risk. Read the
      quote below.
    - It is not known whether this drug is excreted in human milk.
      Source: US FDA label for lactulose (Lactulose), section 'nursing mothers',
      retrieved 2026-08-29
    - Because many drugs are excreted in human milk, caution should be exercised when
      lactulose solution is administered to a nursing woman.
      Source: US FDA label for lactulose (Lactulose), section 'nursing mothers',
      retrieved 2026-08-29
    - Because animal reproduction studies are not always predictive of human response,
      this drug should be used during pregnancy only if clearly needed. 8.3 Nursing
      Mothers It is not known whether this drug is excreted in human milk.
      Source: US FDA label for lactulose (Lactulose), section 'use in specific
      populations', retrieved 2026-08-29