If by SSDI, you mean Social Security Disability Insurance (as opposed to SSI disability), the only health insurance currently available is Medicare A&B (hospital and doctor coverage)and only after you have been on benefits for 24 months. However, beginning 01/2006 Medicare D will begin, (for the elderly and the disabled) and that is the new Prescription coverage offered by the Government. Your state or county may offer Rx coverage and you could check with them for interim help. Check with your local Social Services office, or with your local pharmacy.