Used in the treatment of increased muscle tone associated with spasticity.
Mode of Action
TINA is a central alpha-2-adrenergic receptor agonist and presumably reduces spasticity by increasing presynaptic inhibition of motor neurons. The effects of TINA are greatest on polysynaptic pathways. The overall effect of these actions is thought to reduce facilitation of spinal motor neurons.
Bioavailability: approximately 40%, due to extensive first-pass hepatic metabolism. Mean steady state volume of distribution: 2.4 L/kg and approximately 30% bound to plasma proteins. Half-life of approximately 2.5 hours Approximately 95% of an administered dose is metabolized. The primary cytochrome P450 isoenzyme involved in TINA metabolism is CYP1A2. TINA metabolites are not known to be active; their half-lives range from 20 to 40 hours.
Dosage and Recommendation
The recommended starting dose is 2mg. Because the effect of TINA peaks at approximately 1 to 2 hours post-dose and dissipates between 3 to 6 hours post-dose, treatment can be repeated at 6 to 8 hours intervals, as needed, to a maximum of three doses in 24 hours. Dosage can be gradually increased by 2 mg to 4 mg at each dose, with 1 to 4 days between dosage increases, until a satisfactory reduction of muscle tone is achieved. The total daily dose should not exceed 36mg.
Packing and Presentation
Available in 2/4mg tablet. Each strip contains 10 tablets.