Flexibac

Generic Name: Baclofen

Indications

Flexibac is indicated in-

• spasticity resulting from multiple sclerosis
• flexor spasms and concomitant pain, clonus and muscular rigidity
• skeletal muscle spasm resulting from rheumatic disorders
• spinal cord injuries and other spinal cord diseases
• cerebrovascular accidents or neoplastic or degenerative brain disease

Pharmacology

Baclofen inhibits both monosynaptic and polysynaptic reflexes at the spinal level by stimulating the GABA_B receptors, which inhibits the release of glutamate and aspartate. It may also act at intraspinal sites producing CNS depression. Baclofen also exerts an antinociceptive effect.

Dosage & Administration

Adult & children over 10 years: 5 mg 3 times daily, preferably with or after food, gradually increased; max. 100 mg daily.

Children <10 years: Treatment is usually started with 2.5 mg (2.5 ml) given 4 times daily then raised according to requirement. Daily maintenance dose-

• 12 month-2 years: 10-20 mg (10-20 ml)
• 2 years-6 years: 20-30 mg (20-30 ml)
• 6 years-10 years: 30-60 mg (30-60 ml)

Interaction

• Increased sedation may occur if Flexibac is taken with agents acting on the central nervous system, alcohol or synthetic opiates. The risk of respiratory depression is also increased.
• Combined treatment with Flexibac and antihypertensives is likely to increase the fall in blood pressure; therefore the dosage of antihypertensive medication should be adjusted accordingly.
• The concomitant administration of Flexibac and tricyclic antidepressants may potentiate the pharmacological effects of Flexibac resulting in pronounced muscular hypotonia.
• In patients with Parkinsons disease receiving treatment with Flexibac and levodopa and carbidopa, there have been several reports of mental confusion, hallucinations, headaches, nausea and agitation.
• The concurrent use of MAO inhibitors and Flexibac may result in increased CNS depressant effects. Caution is advised and the dosage of one or both agents should be adjusted accordingly.
• Caution should be exercised when administering Flexibac and magnesium sulphate or other neuromuscular blocking agents since a synergistic effect may theoretically occur.

Contraindications

Baclofen is contraindicated in patients with hypersensitivity to any component of this product.

Side Effects

The most common adverse reactions associated with Flexibac are transient drowsiness, daytime sedation, dizziness, weakness and fatigue.

• Central Nervous System: Headache (<10%), insomnia (<10%), and rarely, euphoria, excitement, depression, confusion, hallucinations, paraesthesia, nightmares, muscle pain, tinnitus, slurred speech, co-ordination disorder, tremor, rigidity, dystonia, ataxia, blurred vision, nystagmus, strabismus, miosis, mydriasis, diplopia, dysarthria, epileptic seizures, respiratory depression.
• Cardiovascular: Hypotension (<10%), rare instances of dyspnoea, palpitation, chest pain, syncope.
• Gastrointestinal: Nausea (approximately 10%), constipation (<10%) and rarely, dry mouth, anorexia, taste disorder, abdominal pain, vomiting, diarrhoea and positive test for occult blood in stool.
• Genitourinary: Urinary frequency (<10%) and rarely, enuresis, urinary retention, dysuria, impotence, inability to ejaculate, nocturia, haematuria.
• Other: Instances of rash, pruritus, ankle oedema, excessive perspiration, weight gain, nasal congestion, visual disturbances, hepatic function disorders and paradoxical increase in spasticity. Muscular hypotonia of a degree sufficient to make walking or movement difficult may occur but is usually relieved by readjusting the dosage. For this purpose, the daytime dosage may be reduced and the evening dosage increased.