Option Care Inc/De Watch

from SC 13D/A 1 page <page> Exhibit 1 Agreement to Jointly File Amendment No. 3 to Schedule 13d the Undersigned Hereby Agree to Jointly Prepare and File With Regulatory Authorities an Amendment No. 3 to Schedule 13d and Any Future Amendments Thereto Reporting Each of the Undersigned's Ownership of Securities of Option Care, Inc. and Hereby Affirm That Such Amendment No. 3 to Schedule 13d Is Being Filed on Behalf of Each of the Undersigned. Dated: January 10, 2002 Ej Financial/Oci Management, L.P. Chicago, Illinois By: Pharma Nevada, Inc. Its Managing General Partner By: /S/ John N. Kapoor John N. Kapoor, President Dated: January 10, 2002 E.J. Financial Investments II, L.P. Chicago, Illinois By: /S/ John N. Kapoor John N. Kapoor Its Managing General Partner Dated: January 10, 2002 E.J. Financial Investments III, L.P. Chicago, Illinois By: /S/ John N. Kapoor John N. Kapoor Its Managing General Partner Dated: January 10, 2002 /S/ Editha Kapoor Chicago, Illinois Editha Kapoor Dated: January 10, 2002 Pharma Nevada, Inc. By: /S/ John N. Kapoor John N. Kapoor, President

from SC 13D/A 1 page <page> Exhibit 1 Agreement to Jointly File Amendment No. 2 to Schedule 13d the Undersigned Hereby Agree to Jointly Prepare and File With Regulatory Authorities an Amendment No. 2 to Schedule 13d and Any Future Amendments Thereto Reporting Each of the Undersigned's Ownership of Securities of Option Care, Inc. and Hereby Affirm That Such Amendment No. 2 to Schedule 13d Is Being Filed on Behalf of Each of the Undersigned. Dated: November 9, 2001 Ej Financial/Oci Management, L.P. Chicago, Illinois By: /S/ John N. Kapoor John N. Kapoor Its Managing General Partner Dated: November 9, 2001 /S/ John N. Kapoor Chicago, Illinois John N. Kapoor

from S-3/A ~50 pages Underwriting Agreement

from SC 13D 1 page <page> Exhibit 1 Agreement to Jointly File Schedule 13d the Undersigned Hereby Agree to Jointly Prepare and File With Regulatory Authorities a Schedule 13d and Any Future Amendments Thereto Reporting Each of the Undersigned's Ownership of Securities of Option Care, Inc. and Hereby Affirm That Such Schedule 13d Is Being Filed on Behalf of Each of the Undersigned. Dated: October 5, 1999 Chicago, Illinois Ej Financial Investments III, L.P. By: /S/ John N. Kapoor John N. Kapoor Its Managing General Partner Dated: October 5, 1999 /S/ John N. Kapoor Chicago, Illinois John N. Kapoor

from SC 13D/A 1 page <page> Exhibit 1 Agreement to Jointly File Amendment No. 1 to Schedule 13d the Undersigned Hereby Agree to Jointly Prepare and File With Regulatory Authorities an Amendment No. 1 to Schedule 13d and Any Future Amendments Thereto Reporting Each of the Undersigned's Ownership of Securities of Option Care, Inc. and Hereby Affirm That Such Amendment No. 1 to Schedule 13d Is Being Filed on Behalf of Each of the Undersigned. Dated: October 5, 1999 Ej Financial/Oci Management, L.P. Chicago, Illinois By: /S/ John N. Kapoor John N. Kapoor Its Managing General Partner Dated: October 5, 1999 /S/ John N. Kapoor Chicago, Illinois John N. Kapoor