Information Notice No. 88-15:Availability of U.S. Food and Drug Administration (FDA)-Approved Potassium Iodide for Use in Emergencies Involving Radioactive Iodine

                                  UNITED STATES
                          NUCLEAR REGULATORY COMMISSION
                             WASHINGTON, D.C.  20555

                                 April 18, 1988

Information Notice No. 88-15:  AVAILABILITY OF U.S. FOOD AND DRUG 
                                   ADMINISTRATION (FDA)-APPROVED POTASSIUM 
                                   IODIDE FOR USE IN EMERGENCIES INVOLVING 
                                   RADIOACTIVE IODINE


Medical, Academic, and Commercial licensees who possess radioactive iodine. 


This notice is intended to provide information on the storage and use of 
potassium iodide as a thyroid blocking agent in incidents involving exposure 
to radioactive iodine.  It is expected that licensees will review this infor-
mation for applicability to their licensed activities and distribute this 
notice to responsible radiation safety staff.  However, suggestions contained 
in this information notice do not constitute new NRC requirements, and no 
written response is required. 

Description of Circumstances: 

During a nuclear pharmacy inspection, NRC and the licensee discussed the 
possibility of maintaining a supply of potassium iodide at each pharmacy 
location.  This supply would be used as a thyroid blocking agent in case of an 
iodine-131 sodium iodide spill with possible personnel contamination.  The 
licensee asked for a statement of NRC's policy regarding on-site storage of 
potassium iodide for use in incidents involving radioactive exposures.  There 
is an NRC and Federal Emergency Management Agency (FEMA) policy addressing 
on-site storage of FDA-approved "radiation emergency potassium iodide" as a 
thyroid blocking agent for power reactor emergency workers (Federal Register, 
Vol. 50, No. 142, p. 30258, July 24, 1985). 


There is no NRC policy on non-reactor licensees using FDA-approved "radiation 
emergency potassium iodide" (i.e., the generic drug nomenclature).  However, 
as discussed below, licensees may wish to provide for its availability in case 
of an emergency. 

.                                                            IN 88-15
                                                            April 18, 1988
                                                            Page 2 of 3

The FDA has evaluated the medical and radiological risks of administering 
potassium iodide for thyroid blocking under emergency conditions.  The FDA has 
concluded that FDA-approved "radiation emergency potassium iodide" is safe and 
effective and has approved it for over-the-counter sale for this purpose 
(Federal Register, Vol. 50, No. 142, p. 30258, July 24, 1985).  FDA guidance 
states that risks of side effects, such as allergic reactions, from the 
short-term use of relatively low doses of potassium iodide for thyroid 
blocking in a radiation emergency, are outweighed by the risks of radioiodine-
induced thyroid nodules or cancer, if the projected dose to the thyroid gland 
is 25 rems or greater.  Because FDA has authorized the non-prescription sale 
of "radiation emergency potassium iodide," it is legally available to organi-
zations or individuals who, based on their own corporate or personal analysis, 
choose to have the drug immediately available. 

At this time, ANBEX, Inc. (Box 863, Radio City Station, New York, NY  10019) 
and Carter-Wallace, Inc. (P.O. Box 1001, Cranbury, NJ  08512) are the only 
companies that have received FDA new drug application (NDA) approval for their 
non-prescription "radiation emergency potassium iodide" drugs.  These drugs 
are not stocked in pharmacies and must therefore be ordered directly from the 
companies.  The non-prescription "radiation emergency potassium iodide" is 
manufactured at the proper adult dosage for thyroid blocking, is readily 
absorbed by the body, and has a package insert providing information on the 
dosage, method of action, warnings and storage.  The directions in the package 
insert should be followed.  Other forms of potassium iodide are available by 
prescription, only. 

Potassium iodide is effective as a thyroid blocking agent.  It reduces thyroid 
gland accumulation of radioiodine that has entered the body through inhalation 
or ingestion if the potassium iodide is administered before, or immediately 
after, exposure to the radioiodine.  If potassium iodide is administered later 
than four hours after an individual has suffered an acute ingestion or in-
halation of radioiodine, its effectiveness as a thyroid blocking agent is less 
than 50 percent.  

If the licensee wants to implement a potassium iodide thyroid blocking 
program, the potassium iodide should be on hand (because it is not readily 
available), and guidelines should be developed to ensure rapid determination 
of whether a radioactive iodine spill or leak warrants administration of the 
potassium iodide.  The guidelines should also address the more detailed 
measurements, surveys, and other followup procedures needed to determine 
whether continued treatment with potassium iodide is needed. 

It is important to stress that the use of potassium iodide is not a substitute 
for preventive measures; e.g., proper handling techniques, control measures, 
and emergency procedures that protect the individual from exposure to radio-
active material. 

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                                                            April 18, 1988
                                                            Page 3 of 3

Licensees are also advised that although FDA has approved "radiation emergency 
potassium iodide" for non-prescription sales, licensees or individuals still 
may wish to consult with a physician about any medical risks of use in an 

No specific action or written response is required by this information notice.
If you have any questions regarding this matter, please contact the person 
listed below or the appropriate NRC regional office. 

                                   Richard E. Cunningham, Director
                                   Division of Industrial and
                                     Medical Nuclear Safety
                                   Office of Nuclear Material Safety
                                     and Safeguards

Technical Contact:  Donna-Beth Howe, NMSS
                    (301) 492-0636

1. Federal Policy on Distribution of Potassium
     Iodide Around Nuclear Power Sites for Use
     as a Thyroidal Blocking Agent
2. List of Recently Issued NRC Information Notices
.                                                            Attachment 2
                                                            IN 88-15
                                                            April 18, 1988
                                                            Page 1 of 1

                             LIST OF RECENTLY ISSUED
                            NRC INFORMATION NOTICES 
Information                                  Date of 
Notice No._____Subject_______________________Issuance_______Issued to________

88-14          Potential Problems with       4/18/88        All holders of OLs
               Electrical Relays                            or CPs for nuclear
                                                            power reactors. 

88-13          Water Hammer and Possible     4/18/88        All holders of OLs
               Piping Damage Caused by                      or CPs for nuclear
               Misapplication of Kerotest                   power reactors. 
               Packless Metal Diaphragm 
               Globe Valves 

88-12          Overgreasing of Electric      4/12/88        All holders of OLs
               Motor Bearings                               or CPs for nuclear
                                                            power reactors. 

88-11          Potential Loss of Motor       4/7/88         All holders of OLs
               Control Center and/or                        or CPs for nuclear
               Switchboard Function Due                     power reactors. 
               to Faulty Tie Bolts 

88-10          Materials Licensees:  Lack    3/28/88        All NRC licensees 
               of Management Controls Over                  authorized to use 
               Licensed Programs                            byproduct 

87-44,         Thimble Tube Thinning in      3/28/88        All holders of OLs
Supp. 1        Westinghouse Reactors                        or CPs for nuclear
                                                            power reactors 
                                                            that employ a 
                                                            Westinghouse NSSS.

88-09          Reduced Reliability of        3/18/88        All holders of OLs
               Steam-Driven Auxiliary                       or CPs for nuclear
               Feedwater Pumps Caused                       power reactors. 
               by Instability of Woodward 
               PG-PL Governors 

88-08          Chemical Reactions with       3/14/88        All NRC licensees 
               Radioactive Waste                            generating or pro-
               Solidification Agents                        cessing low level 
                                                            radioactive waste.
OL = Operating License
CP = Construction Permit 

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