Fluid Intake after I-131

[Guest guest]

....(snip)......

> That's the importance of guzzling water during

> this period - you want to flush out the I-131

> that isn't grabbed by thyroid/cancer cells.

Oops. Not a good idea as someone has already pointed out!

Many of us are given those instructions by hospital personnel, but it's

not prudent advice for thyca patients. Here's Dr. Ain's post on this:

Dear ThyCa Members: (REPOST)

Concerning fluid intake during I-131 therapies:

I typically advise patients (after doses < 250 mCi) to drink

only when thirsty. Attempts to " wash out " the radioiodine are

self-defeating, particularly in the first 48 hours. This is because,

a significant portion of the effective radioiodine recirculates for

additional therapeutic uptake into remnant or tumor tissue. Drinking

large quantities of liquid to cause a forced diuresis actually lowers

the effectiveness of the administered radioiodine.

After doses exceeding 250 mCi, it is advisable to drink 8 oz

of liquid each waking hour and to empty the bladder every two hours,

only for the first day. This is calculated to minimize radiation

dose to the bladder wall and ovaries. Drinking more, or less, actually

increases the radiation dose to these organs. After the first day,

drink when thirsty and urinate when you want. It is quite rare for

patients to require more than 48 hours hospitalization after

radioiodine doses under 200 mCi, unless they have kidney problems.

Our own protocol is to discharge patients (with normal kidney function)

after 24 hours for I-131 doses less than 500 mCi.

**************PLEASE BE ADVISED**********************

THE INFORMATION CONTAINED IN THIS COMMUNICATION IS INTENDED

FOR EDUCATIONAL PURPOSES ONLY. IT IS NOT INTENDED, NOR SHOULD

IT BE CONSTRUED, AS SPECIFIC MEDICAL ADVICE OR DIRECTIONS. ANY

PERSON VIEWING THIS INFORMATION IS ADVISED TO CONSULT THEIR OWN

PHYSICIAN(S) ABOUT ANY MATTER REGARDING THEIR MEDICAL CARE.

*************************************************

B. Ain, M.D.

Associate Professor of Internal Medicine

Director, Thyroid Nodule & Oncology Clinical Service

Director, Thyroid Cancer Research Laboratory

Division of Endocrinology and Molecular Medicine

Department of Internal Medicine, Room MN524

University of Kentucky Medical Center

800 Rose Street, Lexington, Kentucky 40536-0084