Diagnostic Products Corporation Schedules Conference Call to Discuss Fourth Quarter and Year End 2003 Results

LOS ANGELES February 5, 2004—Diagnostic Products Corporation (NYSE:DP) announced today that it has scheduled a conference call to discuss the Company's financial results of its fourth quarter quarter and year end 2003 on Friday, February 13, 2003, at 11:30 a.m. Eastern time (8:30 a.m. Pacific time).

The Company plans to release its financial results before the market opens on Friday.

If you are interested in participating in the call, please call (800) 260-6066 on the day of the conference, at least ten minutes prior to the conference in order for the operator to tie you into the call. The operator will ask you to identify the call with the company name Diagnostic Products-Jim Brill.

An "instant replay" of the call will be available until February 23. If you would like to take advantage of this special service, you can access it via (800) 839-6713 and the code: "6102715." It usually takes two hours following the conference to set up the recording.

Founded in 1971, Diagnostic Products Corporation (DPC) is the global leader dedicated exclusively to immunodiagnostic testing. The Company's product menu includes over 400 automated and nonautomated tests to measure microorganisms, hormones, drugs and other medically important substances present at infinitesimal concentrations in body fluids and tissues. DPC also designs and manufactures automated laboratory instrumentation, which provides fast, accurate results while reducing labor and reagent costs. DPC sells its products to hospitals, clinics and laboratories domestically and in over 100 other countries. Additional Company information can be found on DPC's website at www.dpcweb.com.

Except for the historical information contained herein, this press release contains forward- looking statements that involve risks and uncertainties that could cause actual results to differ materially. These factors include the effects of governmental or other actions relating to the Company's Chinese subsidiary; the rate of customer demand for the Company's products; the Company's ability to successfully market new and existing products; its dependence on certain suppliers; domestic and foreign government regulation; its ability to keep abreast of technological innovations and to translate them into new products; competition; political and economic instability in certain markets including the movements of foreign currencies relative to the dollar; and other risks and uncertainties disclosed from time to time in the Company's SEC reports and filings.