|Composition||Pregabalin 75mg and Nortryptyline 10mg Tablets|
|Mechanism of Action||
Pregabalin is an analog of the neurotransmitter GABA. It binds potently to the α2-δ subunit resulting in modulation of Ca channels and reduction in the release of several neurotransmitters, including glutamate, norepinephrine, serotonin, dopamine, calcitonin gene-related peptide and substance P.
Absorption: Rapidly absorbed. Bioavailability: Approx 90%. Time to peak plasma concentration: W/in 1.5 hr. Distribution: Volume of distribution: 0.5 L/kg. Not bound to plasma protein.
Metabolism: Negligible metabolism.Excretion: Via urine (approx 98%) as unchanged drug). Elimination half-life: 6.3 hr.
Somnolence, dizziness, headache, diplopia, blurred vision, vertigo, fatigue, irritability, arthralgia, muscle cramp, back and limb pain, cervical spasm, disorientation, insomnia, nasopharyngitis, ataxia, tremor, dysarthria, amnesia, paraesthesia, hypoaesthesia, lethargy, sedation, oedema, peripheral oedema, dry mouth, constipation, diarrhoea, vomiting, nausea, flatulence, abdominal distension, increased appetite, wt gain, euphoria, confusion, reduced libido, erectile dysfunction; attention, memory, coordination and gait disturbances; fall, feeling drunk, abnormal feeling. Rarely, Stevens-Johnson syndrome, rhabdomyolysis, breast enlargement, gynaecomastia. Potentially Fatal: Angioedema.
Patient w/ history of angioedema episodes, severe CV disease, renal impairment. Avoid abrupt withdrawal. Pregnancy and lactation. Patient Counselling May impair ability to drive, operate machinery or engage in hazardous activities. Monitoring Parameters Monitor visual disturbances. Closely observe for clinical worsening, suicidality and unusual changes in behaviour
Adult: Initially, 150 mg/day, may increase to 300 mg/day after 3-7 days. Max: 600 mg/day after a 7-day interval. All doses to be given in 2 or 3 divided doses.
Renal impairment: Haemodialysis: 25-100 mg immediately after each 4-hr haemodialysis session.