ethambutol (Rx)

Brand and Other Names:Myambutol
  • Print

Dosing & Uses

AdultPediatric

Dosage Forms & Strengths

tablet

  • 100mg
  • 400mg
more...

Tuberculosis

Prescribing information

  • Initial TB treatment: 15 mg/kg PO qDay
  • Prior TB treatment: 25 mg/kg PO qDay; after 60 days, decrease to 15 mg/kg PO qDay

Daily administration

  • Guidelines from American Thoracic Society (ATS), Centers for Disease Control and Prevention (CDC), and the Infectious Diseases Society of America (IDSA)
  • 40-55 kg: 800 mg PO
  • 56-75 kg: 1.2 g PO
  • >75 kg: 1.6 g PO

Twice weekly administration

  • Guidelines from American Thoracic Society (ATS), Centers for Disease Control and Prevention (CDC), and the Infectious Diseases Society of America (IDSA)
  • 40-55 kg: 2 g PO
  • 56-75 kg: 2.8 g PO
  • >75 kg: 4 g PO

3x per week administration

  • Guidelines from American Thoracic Society (ATS), Centers for Disease Control and Prevention (CDC), and the Infectious Diseases Society of America (IDSA)
  • 40-55 kg: 1.2 g PO
  • 56-75 kg: 2 g PO
  • >75 kg: 2.4 g PO

Disseminated MAC (Off-label)

Treatment: 15 mg/kg PO qD

Prophylaxis: use same dose with other antibiotics

Pulmonary M. Avium Complex (MAC) without HIV (Off-label)

25 mg/kg PO qD; after 60 d, decrease to 15 mg/kg PO qD

Other Indications & Uses

Tuberculosis: intended to be used concomitantly with other anti-TB drugs; usually isoniazid initially; subsequently, use second-line anti-TB drugs

Off-label: MAC infections

Dosage Forms & Strengths

tablet

  • 100mg
  • 400mg
more...

Tuberculosis

Prescribing information

  • Use not recommended in patients <13 years, but has been used in peds

ATS, CDC, and IDSA

  • Guidelines from American Thoracic Society (ATS), Centers for Disease Control and Prevention (CDC), and the Infectious Diseases Society of America (IDSA)
  • 15-20 mg/kg/day PO; not to exceed 1 g/day OR 
  • 50 mg/kg PO 2x/week; not to exceed 2.5 g/dose

AAP

  • Guidelines from the American Academy of Pediatrics (AAP)
  • 15-25 mg/kg/day PO; not to exceed 1 g/day OR 
  • 50 mg/kg PO 2x/week; not to exceed 2.5 g/dose

Disseminated MAC, Prophylaxis (Off-label)

As adult, 15 mg/kg PO qDay combined with other drugs; not to exceed 1 g/day

Next:

Interactions

Interaction Checker

and ethambutol

No Results

     activity indicator 
    No Interactions Found
    Interactions Found

    Contraindicated

      Serious - Use Alternative

        Significant - Monitor Closely

          Minor

            All Interactions Sort By:
             activity indicator 
            Previous
            Next:

            Adverse Effects

            Frequency Not Defined

            Acute gout or hyperuricemia

            Abdominal pain

            Anaphylaxis

            Anorexia

            Confusion, disorientation

            Fever

            Headache

            LFT abnormalities

            Malaise

            Nausea

            Optic neuritis; symptoms may include decreased acuity, color blindness or visual defects (usually revrsible with discontinuation, though irreversible blindness has been reported)

            Peripheral neuritis

            Pruritis

            Rash

            Vomiting

            Previous
            Next:

            Warnings

            Contraindications

            Optic neuritis

            Hypersensitivity

            Cautions

            See pkg insert for complete dosage info

            < 5 yo: may be difficult to monitor visual acuity

            Previous
            Next:

            Pregnancy & Lactation

            Pregnancy Category: B

            Lactation: enters breast milk; use with caution (AAP Committee states "compatible with nursing")

            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...
            Previous
            Next:

            Pharmacology

            Mechanism of Action

            Interferes with metabolite production in Mycobacterium

            Absorption

            Bioavailability: ~80%

            Peak Plasma Time: 2-4 hr

            Distribution

            Widely throughout body; concentrated in kidneys, lungs, saliva, and red blood cells

            Relative diffusion from blood into CSF: Adequate with or without inflammation (exceeds usual MICs)

            CSF:blood level ratio: 0% (normal meninges); 25% (inflamed meninges)

            Protein binding: 20-30%

            Metabolism

            Hepatic (20%) to inactive metabolite

            Elimination

            Half-life elimination: 2.5-3.6 hr; 7-15 hr (end-stage renal disease)

            Excretion: ~50% urine; ~20% feces as unchanged drug

            Previous
            Next:

            Images

            Previous
            Next:

            Formulary

            FormularyPatient Discounts

            Adding plans allows you to compare formulary status to other drugs in the same class.

            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.
            Additional Offers
            Email to Patient

            From:

            To:

            The recipient will receive more details and instructions to access this offer.

            By clicking send, you acknowledge that you have permission to email the recipient with this information.

            Email Forms to Patient

            From:

            To:

            The recipient will receive more details and instructions to access this offer.

            By clicking send, you acknowledge that you have permission to email the recipient with this information.

            Previous