Baclofen

Generic name
Baclofen
Brand name
ATC Code
M03BX01
Dosages
Side effects in children
Warnings & precautions in children
Contra-indications in children

Interactions
PK
Renal impairment
References

Pharmacokinetics in children

The following kinetic parameters have been observed in children aged 2-12 years after an oral dose of 2.5 mg:

Cl: 315.9 ml/hour/kg
Vd: 2.58 l/kg
T½: 5.1 hours
Tmax: 0.95-2 hours

dose recommendation of formulary compared to licensed use (on-label versus off-label)

No information is present at this moment.

Available formulations

No information is present at this moment.

Dosages

Muscle spasms
  • Oral
    • 3 months up to 8 years
      • Initial dose: 0.3 mg/kg/day in 4 doses.
      • Maintenance dose: Increase step by step by 0.3 mg/kg/day to 0.75 - 2 mg/kg/day in 4 doses. Max: 40 mg/day.

      • Extramural: increase every 14 days
        Intramural: increase every 3-7 days

    • 8 years up to 18 years
      • Initial dose: 0.3 mg/kg/day in 4 doses.
      • Maintenance dose: Increase step by step by 0.3 mg/kg/day to 0.75 - 2 mg/kg/day in 4 doses. Max: 60 mg/day.

      • Extramural: increase every 14 days
        Intramural: increase every 3-7 days
Spierspasmen van cerebrale of spinale oorsprong
  • Intrathecal
    • ≥ 4 years

      • Initial dose: test dose 25-50 mcg/day intrathecally; depending on the response, increase by 25 mcg every 24 hours to a maximum of 100 mcg.
        Maintenance dose:
        Effect of the test dose < 12 hours: double the effective test dose, administer over 24 hours.    
        Effect of the test dose > 12 hours: effective test dose, over 24 hours.
        After the first 24 hours, slowly adjust the dose daily in steps of max. 5-15% of the daily dose. Max. 1000 mcg/day

Renal impaiment in children > 3 months

When used orally:

  • GFR ≥ 50 ml/min/1.73 m2: dose adjustment is not necessary.
  • GFR 30-50 ml/min/1.73 m2: 100% of normal reversal dose, interval between 2 doses: 24 hours, then dose according to effect and side effect.
  • GFR 10-30 ml/min/1.73 m2: 100% of normal reversal dose, interval between 2 doses: 24 hours, then dose according to effect and side effect.
  • GFR <10 ml/min/1.73 m2: general advice is not given.

When used intrathecally: dose adjustment is not necessary.

Clinical consequences

With impaired renal function, the renal clearance of baclofen decreases. This increases the risk of adverse reactions.

Clinical Effects:

Characteristic symptoms of overdose include central nervous system depression, respiratory depression, convulsions, myoclonia, muscle weakness, and hypotonia and hyporeflexia.

The complete list of all undesirable drug reactions can be found in the national Summary of Product Characteristics (SmPC) – click here

Side effects in children

Sedation (particularly at the start of treatment), vomiting and diarrhoea.

The complete list of all contra-indications can be found in the national Summary of Product Characteristics (SmPC) – click here

Contra-indications

No information available on specific contra indications in children.

The complete list of all warnings and precautions can be found in the national Summary of Product Characteristics (SmPC) – click here

Warnings & precautions in children

Reduce the dose in muscular hypotonia. Down titrate the dosage when stopping after long-term therapy.

Interactions

The complete list of all interactions can be found in the national Summary of Product Characteristics (SmPC) – click here

MUSCLE RELAXANTS, CENTRALLY ACTING AGENTS

This pages provides a list of drugs from the same ATC class for comparison. This does not necessarily mean that these drugs are interchangeable.

References

  1. Rademaker C.M.A. et al, Geneesmiddelen-Formularium voor Kinderen, 2007
  2. Novartis Pharma BV, SPC Lioresal (RVG 06347), www.cbg-meb.nl, Geraadpleegd 26 mei 2010, http://db.cbg-meb.nl/IB-teksten/h06347.pdf
  3. Sintetica GmHb, SmPC Baclofen (RVG 120889) 06-09-2018, www.geneesmiddelinformatiebank.nl
  4. NKFK Workinggroup Acute Kidney Impairment, Extrapolation of KNMP risk analysis "Impaired renal function" for adults to children, 20 Dec 2021

Changes

Therapeutic Drug Monitoring


Overdose