EXCLUSIVE

Legendary actress Debbie Reynolds was hospitalized in L.A. over the weekend following a bad reaction to meds -- Debbie's rep tells TMZ.

According to her rep, 80-year-old Debbie was hospitalized at Cedars-Sinai "due to an adverse reaction she experienced to a medication she was currently taking." It's unclear what kind of medication did the job.

Sounds pretty serious too -- Debbie's rep tells us, the actress has been forced to cancel her upcoming appearances for the next three months.