How to treat with a little mental retardation left as after effects of bacterial meningitis? how can i help myself? any therapy? any medication?

Time will tell: Even after the best therapy, bacterial meningitis may leave some permanent or long term effects which may improve over time. The key is to have patience , and to optimize your health with a diet and exercise. After all, your body has been affected by what one may consider to be a "typhoon" or "tornado". In such areas of the world, it will take time to rebuild- this goes the same for your brain.