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lactulose (Rx)Brand and Other Names:Enulose, Kristalose, more...Constulose, Generlac

 
 
 

Dosing & Uses

AdultPediatric

Dosage Forms & Strengths

oral/rectal solution

  • 10g/15mL

packet

  • 10g
  • 20g
more...

Constipation

Solution: 15-30 mL (10-20 g) PO once daily; may be increased to 60 mL (40 g) once daily

Crystals: 10-20 g PO qDay; may increase to 40 g/day

Portal Systemic Encephalopathy

Prophylaxis

30-45 mL (20-30 g) PO q6-8hr, adjusted until 2-3 soft stools/day; if acute, may be given q1-2hr until 2-3 soft stools/day

Treatment

20-30 g (30-45 mL) PO q1hr to induce rapid defecation; reduced to 20-30 g q6-8hr after defecation achieved; titrated to produce 2-3 soft stools/day

300 mL (200 g) PR with 700 mL water or NS, retained for 30-60 minutes; may be repeated q4-6hr; transition to oral treatment before discontinuance of rectal administration

Dosage Forms & Strengths

oral/rectal solution

  • 10g/15mL

packet

  • 10g
  • 20g
more...

Constipation

0.7-2 g/kg/day (1-3 mL/kg/day) PO in divided doses; not to exceed 40 g/day (60 mL/day)

Portal Systemic Encephalopathy

Prophylaxis

Infants: 2.5-10 mL/day (1.7-6.67 g/day) PO in divided doses; titrated to produce 2-3 soft stools/day

Children and adolescents: 40-90 mL/day (26.7-60 g/day) PO in divided doses; titrated to produce 2-3 soft stools/day

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Interactions

Interaction Checker

lactulose and

No Results

     
     activity indicator 
    No Interactions Found
    Interactions Found

    Contraindicated

      Serious - Use Alternative

        Significant - Monitor Closely

          Minor

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            Adverse Effects

            Frequency Not Defined

            Dehydration

            Diarrhea

            Excessive bowel activity

            Hypernatremia

            Hypokalemia

            Nausea

            Vomiting

            Abdominal cramping

            Abdominal distention

            Belching

            Flatulence

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            Warnings

            Contraindications

            Galactosemia (patients require low-galactose diet)

            Cautions

            Diabetes (preparation contains lactose and galactose)

            Monitor for electrolyte imbalance when drug is used for >6 months or in patients predisposed to electrolyte abnormalities

            Avoid using other laxatives concomitantly

            Inadequate response possible when taken concomitantly with anti-infective

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            Pregnancy & Lactation

            Pregnancy category: B

            Lactation: Unknown whether drug is distributed into milk; use with caution

            Pregnancy Categories

            A:Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

            B:May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

            C:Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

            D:Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

            X:Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

            NA:Information not available.

            more...
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            Pharmacology

            Mechanism of Action

            Constipation: Hyperosmotic agent increases stool water contents, softens stool, promotes peristalsis, and reduces blood ammonia concentration

            Portal systemic encephalopathy: Breakdown of lactulose to organic acids by colonic bacteria acidifies colonic contents, thereby subsequently inhibiting diffusion of ammonia back to blood; agent also enhances diffusion of NH3 from blood into gut, where it is converted to NH4+

            Absorption

            Bioavailability: <3% absorbed

            Onset: 24-48 hr

            Metabolism

            Absorbed lactulose is not metabolized; unabsorbed lactulose is extensively metabolized to organic acids by colonic bacteria

            Metabolites: Lactic acid (main), formic acid, acetic acid (all active)

            Elimination

            Excretion: Urine (absorbed lactulose), feces and bile (unabsorbed lactulose and metabolites; minimal)

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            Images

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            Formulary

            FormularyPatient Discounts

            To view formulary information first create a list of plans. Your list will be saved and can be edited at any time.

            Adding plans allows you to:

            • View the formulary and any restrictions for each plan.
            • Manage and view all your plans together – even plans in different states.
            • Compare formulary status to other drugs in the same class.
            • Access your plan list on any device – mobile or desktop.

            The above information is provided for general informational and educational purposes only. Individual plans may vary and formulary information changes. Contact the applicable plan provider for the most current information.

            Tier Description
            1 This drug is available at the lowest co-pay. Most commonly, these are generic drugs.
            2 This drug is available at a middle level co-pay. Most commonly, these are "preferred" (on formulary) brand drugs.
            3 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs.
            4 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            5 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            6 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            NC NOT COVERED – Drugs that are not covered by the plan.
            Code Definition
            PA Prior Authorization
            Drugs that require prior authorization. This restriction requires that specific clinical criteria be met prior to the approval of the prescription.
            QL Quantity Limits
            Drugs that have quantity limits associated with each prescription. This restriction typically limits the quantity of the drug that will be covered.
            ST Step Therapy
            Drugs that have step therapy associated with each prescription. This restriction typically requires that certain criteria be met prior to approval for the prescription.
            OR Other Restrictions
            Drugs that have restrictions other than prior authorization, quantity limits, and step therapy associated with each prescription.
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