Baclofen is an effective muscle relaxant and antispastic agent with a spinal site of action. Baclofen is structurally similar to the inhibitory neurotransmitter gamma-amino-butyric acid, though its actions are different. It binds stereospecifically to GABA-B receptors. It is thought that activation of the GABA-B receptors on presynaptic terminal reduces evoked transmitter release, perhaps through reduced presynaptic Ca2+ influx. Baclofen can inhibit the function of inward calcium currents in some cells. The drug is rapidly absorbed after oral administration and is widely distributed throughout the body.
Adult: The determination of optimal dosage requires individual titration. The following dosage titration schedule is suggested:
5 mg t.i.d. for 3 days
10 mg t.i.d. for 3 days
15 mg t.i.d. for 3 days
20 mg t.i.d. for 3 days
Thereafter additional increases may be necessary but the total daily dose should not exceed a maximum of 80 mg daily (20 mg q.i.d.). The lowest dose compatible with an optimal response is recommended.
Children: Treatment should be started at a very low dose, e.g., 0.3 mg/kg per day in divided (preferably 4) doses. The dosage should be raised cautiously at 1-2 week intervals until it is sufficient for the child’s individual needs. The usual dosage range for maintenance therapy is 0.75 to 2 mg/kg body weight per day. In children aged over 10 years a maximum daily dose of 2.5 mg/kg body weight may be given.
Alcohol and other CNS depressants may exacerbate the CNS effects of Baclofen and should be avoided. There may be increased weakness if Baclofen is given to patients taking a tricyclic antidepressant and an increased hypotensive effect if it is given to patients receiving antihypertensive therapy.
Baclofen is contraindicated in patients with hypersensitivity to any component of this product.
The most common side effects include drowsiness, nausea, dizziness, lassitude, lightheadedness, confusion, fatigue, muscular pain & weakness and hypotension.
Pregnancy Category C. There are no adequate and well-controlled studies in pregnant women. Baclofen should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. In mothers treated with oral Baclofen in therapeutic doses, the active substance passes into the breast milk. Therefore, administration to nursing mothers is not recommended.
Baclofen should be used with caution in patients who use their spasticity to maintain posture or to increase function. In patient with epilepsy, the clinical state and electroencephalogram should be monitored at regular intervals, since deterioration in seizure control and EEG have been reported occasionally in patient taking Baclofen. Because possibility of sedation, patient should be cautioned regarding the operation of automobiles or other dangerous machinery and activities made hazardous by decreased alertness. Patient should be cautioned that the CNS depressant effects of Baclofen may be additive to those of alcohol and other CNS depressants.
Prominent features are signs of central nervous system depression. No specific antidote of Baclofen is known. Elimination of the agent from GI tract, artificial respiration, administration of fluid with a diuretic and dialysis should be considered.
Renal Insufficiency: Baclofen is excreted principally in urine as unchanged drug. So it may be necessary to reduce the dosage in patients with impaired renal function.
Store in cool & dry place, away from children