Nuclear Cat Poop

I131 is a smart bomb that detonates inside the thyroid

August 4, 2014 (published)

Photo by Dr. Tony Johnson

I have a cat.

Since I’m a veterinarian, that probably doesn’t come as a big surprise to many.

But I have a...radioactive cat!

That’s right – I have a dyed-in-the-wool, glowing green, isotope-emitting, half-life-y radioactive cat. And I paid actual money to make him that way.

Lemme ‘splain.

Crispy, the isotope-y cat of the hour, has had a rough life. He is currently about 15, but at the tender age of 2 or 3, some antisociopathic troglodytic knuckle-dragger with a can of lighter fluid and the will to use it set him aflame (and then was promptly captured and ground down into a fine powder, which I sprinkle on my oatmeal daily...I mean incarcerated. That other part was just a dream of mine.)

Anyway, he was set on fire, but recovered and other than a scarry head that would make Freddy Krueger envious, he’s more or less normal. Normal until a few months ago, when my wife, the smarter and better looking of our little world of two, noticed that the litter boxes were filling up with extra bonus pee and the water dish was getting as dry as a really dry thing (sometimes analogies fail me).

To a veterinarian, drinking too much water and forming too many piss biscuits in the litter box leads us to a short and fairly unhappy list of diseases: diabetes, kidney failure, liver failure, some adrenal gland disorders, hyperthyroidism and a smattering of lesser diseases. So we were a might alarmed, and after a round of Rock-Paper-Scissors to see who would haul him in for blood work (I won), she took him in and we discovered that he was hyperthyroid.

Given the baddies on that list, hyperthyroidism isn’t all that bad. We were secretly hoping for it to be a phenomenon known as "psychogenic polydipsia," which is just medicalese for “he’s drinking more water than he should because he likes to," but as far as diseases go, hyperthyroidism is pretty mild. Except for the radiation, which I will get to in a bit.

When your thyroid gland decides to go all whoopsy and hyper, it's like the accelerator pedal on your metabolism is pressed to the floor. No one really knows what causes it. It’s like one morning, it just wakes up, downs three venti lattes and says “I’m working overtime today!” and starts churning out abnormally high levels of thyroid hormone, the substance that regulates how fast you burn energy. The cause is elusive, and everything from space rays to preservatives in pet food has been blamed, but the reality is in most cases it just does this spontaneously. Most cats with hyperthyroidism lose weight, eat ravenously and drink and pee too much. Crispy, ever the iconoclast, only did the last bit with the water, the peeing and such, but we caught it early and his levels were only mildly high.

Years ago, one of the few options for therapy was to have a madman with a scalpel go in and cut the darn hyperactive thing out. The problem is that the thyroid glands sit right atop some important nerves, and, like a game of Operation, has wee little secondary glands within it that get upset when these tiny giblets (creatively known as parathyroid glands) are yanked along with the thyroid gland. There is also a medication called methimazole that is every bit as hard to administer as it is to pronounce. Luckily for Crispy, treatment has advanced of late.

The current treatment of choice is radioactive iodine, also known by the less scary and cuddlier moniker I131. Iodine is taken up by the thyroid and forms a core portion of the thyroid hormone molecule. When you attach a little radioactive bit to some regular old iodine, it becomes a thyroid smart bomb and detonates right inside the thyroid, destroying the overactive gland. If it is dosed just right, it leaves enough normal gland to still provide some thyroid function. It’s not unheard of for cats (and humans, too – this treatment is used in people with hyperthyroidism) to swing from hyperthyroid to hypothyroid and need thyroid supplements, but the ideal end result is destruction of the excess tissue only.

Once we had a diagnosis, we signed Crispy up for treatment at a nearby clinic. The actual nuts and bolts aspect of the treatment is ridiculously simple: wearing lead-lined gloves and in a special room, a technician trained in the ways of nuclear medicine injects the stuff in the scruff of the neck, lovingly tosses him in a lead-lined cage for three days and the I131 does all the rest. He gets to cool his heels (literally) for a little 72-hour radiation vacation and then gets to come home, as long as the Geiger counter agrees that he’s no longer (all that) radioactive. When we picked him up after all was said and done, he shrugged his shoulders and said “Meh” when we asked him how his stay was.

Most of the radiation was gone from his body by the time he was picked up, but the discharge instructions still offer some vaguely ominous warnings against overly close cuddling for 2 weeks, and some instructions for handling the selfsame piss biscuits that started this whole episode; most of the radiation is eliminated through urine and feces, while some just evaporates into the cosmos. We set him up with a little Chernobyl-esque dacha in the basement for his two weeks, and bought the special litter required for safe handling of his nuclear waste.

All went well, but as I scooped the odd, flushable waste, a couple of scenarios started to form in my mind. The litter was made of wheat (somehow) and formed these gooey, pancake-like clumps that allegedly could be flushed down the commode. First, I pictured the residual radiation getting into the local water supply and leading to a horde of sentient fish from nearby streams with opposable fins walking up my driveway and ringing the doorbell, wanting to have a word with me about my environmental sensibilities. Once I convinced myself that this was unlikely to happen, as the local lakes are devoid of fish, I became concerned that “flushable” might be a relative term and that I was filling up the bowl with too much at one time.

In my mind, a scene like the one from Fantasia where sorcerer Mickey overfills legions of (sentient, opposable) buckets from the enchanted well started to take shape. One scoop too many, one flush of the flush-knob (does that thing have a name?) and a wheaty brown mess started to overflow the bowl with alarming, nuclear speed. I pictured myself doing all the desperate things you do when a toilet overflows – the mad scramble for towels, old T-shirts, anything that would soak up the mess, the rapid-fire removal of the toilet top to press the little floaty bar thing to stop the bowl from filling more, the cramped and uncomfortable grab for the knobby bit that allows water to flow into the reservoir thing that is stopped by the floaty bar thing…

In that moment, I realized that I don’t know many of the names for toilet parts.

Next, I pictured the inevitable call to the water damage restoration company:

“Hello, Psychogenic Polydipsia Water Damage Restoration Company.”

“Hi there. My toilet just overflowed and I need a plumber and someone to come out and deal with the water damage.”

“Certainly, sir. We can help you with that. There is a surcharge if this is soiled water, due to the contamination hazard. Was the toilet full at the time?”

(Up to this point, this is a nearly verbatim representation of an actual conversation I had once when a toilet overflowed. After this point, it’s all wheels turning in my tortured brain.)

“Well, yes. It had cat poop and pee in it.”

“Ah, I see. Animal waste carries an extra sur-surcharge, due to the contamination hazard.”

“Ummm, OK. I need to get to this cleaned up, so I guess I’ll have to pay it. There is one more thing, though.”

“What’s that, sir?”

“The waste is...radioactive.”


Luckily for me, my family and all the nearby sentient, opposably-finned fish, the toilet did not overflow, the restoration company did not need to be summoned and all the peepee pancakes swirled merrily down the tubes without incident. It was all a dream. A fevered, radioactive, Three-Mile-Island dream.

Crispy is just about done with his 2-week period of home isolation, and we can let him rejoin the family fairly soon. All in all, it was worth it, and certainly better than a lifetime of bitter pills or surgery. If only I can get the specter of those sentient fish and the overflowing, radioactive toilet out of my mind, I think life will return to normal for all of us.

Now, I just need to get the manual and learn the names for some toilet parts.


November 12, 2017

I am planning on having my cat treated.  I live in an apartment and cannot keep the litter box in the bathroom but would have to carry it into the bathrm. to flush the turds, etc.  I too had your thoughts.  The alternative is to store it in a closet in closed bags for two weeks and then throw it out in the regular garbage.  I live in a big city and they hv radioactive detectors, (poor verbiage) so the ve said it's best to flush.  I'm concerned about carrying box w/ radiation to bathroom several times/day; possibly breathing small particles of radioactive dust, etc. as I put it in the toilet.  One place said to keep turds for 3 months, another said for 2 weeks and then OK to throw out...any thoughts doctor?  Thanks. Chandler.

Christy Corp-Minamiji, DVM 
September 29, 2014

Hi Ginny.  We're so glad you enjoyed the articles.  We think Dr. Johnson is pretty funny, too.  We don't have a mailing list, but you can follow VetzInsight on Facebook or Twitter or subscribe to the RSS feed (icons for all of these are on our front page) to find new articles.  In general, a new article posts every Monday.  Welcome to the community, and thanks for your feedback!

Ginny Boudwin 
September 27, 2014

What incredible writing! I was laughing my face off after reading several articles. Thanks for sharing with a very creative touch. You must be a riot to be around! I am the owner of a crazy cat named Dennis. Love him to Death! Your articles make him even funnier. Keep up the great writing and put me on your mailing list please!!!!!!


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