For the past ten months, I’ve been taking part in a drug experiment. Along with 47 other people around the country, I’m taking a medication called Tolvaptan, which may or may not end up lessening the effects of polycystic kidney disease, also known as PKD. PKD is the most common genetic, life-threatening disease there is — more common than cystic fibrosis, muscular dystrophy, Huntington’s disease, hemophilia, Down syndrome and sickle cell anemia combined.
I inherited PKD from my dad; a number of other close relatives have it, too. Each year our family takes part in the PKD Foundation’s Walk for the Cure, raising money that will help pay scientists to research this disease ever more deeply. Thanks to the PKD Foundation and its many benefactors, the research is going extremely well. But we’re not there yet.
Tolvaptan is a vasopressin receptor antagonist. Vasopressin is a hormone that causes your kidneys to conserve water. Hence, when you take Tolvaptan, fluid flows out of you like, well, water. You pee more, and more often, than other people do. Your body misses all that fluid, so you also get thirstier than you ever used to be. Most mornings when I wake up, I’m thirstier than I was when I hiked the Grand Canyon, some 15 years ago, on a very hot day. I no longer go to sleep without a big glass of water near the bed; when I wake up, I drain it.
A lot of people who care about PKD are curious about Tolvaptan — how it feels to be on it, how optimistic we are. Ever since the invention of dialysis and transplants, Tolvaptan is the first real hope we’ve had. So I’d like to start blogging about it. I may forget to do so, now and again. If you’d like me to say more, just let me know.
For now I’ll say this: I’ve gotten used to peeing more than most people do, and to being thirstier than I ever used to be. I am now constantly aware of where I can get water and juice in a hurry; when I go to a new place, that’s what I look for. When I went to Italy in August, a week or so after the British government disrupted the plot to use liquids to blow up planes in the sky, and the airlines decided that the rest of use could no longer bring liquids onto planes, I became very agitated. I worried much more about getting enough to drink on the plane than about terrorism. (In the end, I was fine. And Italy was even more beautiful than I’d been told it would be.)
There’s an unexpected benefit of Tolvaptan: The thirst, and the anticipation of that thirst, can distract you from other anxieties (exploding planes) you might otherwise develop. I don’t mind my airplane exploding, as long as I have access to liquids on the way down.
I live in New York City — Brooklyn, to be precise — and as the northern hemisphere once again tilts away from the sun, I remember noticing, last year, that I felt colder than I used to feel. Perhaps because of Tolvaptan, my body doesn’t run as warmly as it used to. All of my life, I have felt warm when others around me felt cold. Now I feel cold before they do. That’s a bummer.
But if Tolvaptan slows the growth of my cysts, I’ll take it.