My Father Was Diagnosed With Parkinsons A Year Ago. He

My father was diagnosed with Parkinsons a year ago. He has been put on Syndopa plus and pramipex .5mg, pacitane 2mg, eprtal .5mg yet there seems to be no change in the shaking. his speech is normal, tremor at rest right left, flexed postural, bradykinesia, cogwheel rigidity fundus normal eye movement normal plantar responce flexor. please suggest me what can now do, which medicine is good for him.