The Food and Drug Administration (FDA) requests voluntary reporting of adverse events that may be related to the use of drugs or other medical devices that it regulates. Adverse events related to the use of vaccines are to be reported to  the Vaccine Adverse Event Reporting System (VAERS), which is co-sponsored by the Centers for Disease Control and Prevention (CDC). All other adverse events are to be reported to MEDWATCH.

Report serious adverse events that may be related to the use of:

(1) medications (events termed adverse drug reactions, or ADRs)

(2) medical devices

(3) special nutritional products

(4) vaccines

(5) other products regulated by the FDA (medical software, etc.)


FDA classification of serious event: one or more of the following:

(1) fatal

(2) life-threatening

(3) persistent or significant disability or incapacity

(4) requires or prolongs hospitalization

(5) congenital anomaly or birth defect

(6) requires intervention to prevent an outcome listed above


Reporting should be done even when:

(1) it is uncertain that the medication, device or product caused the adverse event

(2) all of the relevant details are not available

(3) a person is not directly involved in the incident


All reports are treated confidentially, with complete protection of patient identity and information.


Vaccine Adverse Event Reporting System (VAERS):

• mail: VAERS, PO Box 1100, Rockville, MD, 20849-1100

• phone: 800-822-7967, or 301-217-9660, or 301-827-3974

• fax: 301-827-3529

• e-mail: VAERS@CAIS.COM

• CDC VAERS website: www.cdc.nip/VAERS.html

• FDA VAERS website:



• mail: MEDWATCH, 5600 Fishers Lane, Rockville, MD, 20852-9787

• phone: 800-FDA-1088

• fax: 800-FDA-0178

• website:



• This means of reporting may not detect adverse events widely separated in time from the original use of the implicated drug or device.

• A drug or device may be implicated when it is not causal for the adverse event.

• Reporting bias may affect what adverse events are reported and when.

• Information may be incomplete or unverified.

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