Every state has different provision in this regard. It is not deducted in all the states of India.
use google search to find out the exemptions available in every state
in Maharashtra exemption is available if certificate by GOVT HOSPITAL PRODUCED STATING THAT THE DISABILITY IS MORE THAN 40%.
Profession Tax Exempted Individuals in Maharashtra
The following persons are exempted from the provisions of the Profession Tax Act in Maharashtra :
Senior Citizen above 65 years age.
Handicapped Person with more than 40 % disability or parent of a physically disabled or mentally retarded child.
Read more: http://www.taxguru.in/mvat/new-profession-tax-rates-after-mahrashtra-government-budget.html#ixzz0xocGIvVa