Does Walmart in San Jose Costa Rica have distilled water

I am traveling to Costa Rica in a few weeks with United Airlines and I have 2 questions.
1: I tried to ask United if I could bring my Distilled water as check baggage as an extra bag for no charge as it is a medical
Necessity similar to a,wheel chair as sleep apnea is a disability (maybe stretching it) but I got a canned response and I couldn't find a direct phone number to call them directly from Canada. I know I can carry a gallon through security with my CPAP prescription. Other airlines I have flown let me ship the water in a separate box for no charge.

2: Does anyone have experience getting distilled water in Costa Rica? I know I can use any bottled water but I use my distilled water unheated for sinus rinses also. I see they have Walmart in San Jose. I have also read where you get distilled water in the automotive section in some countries. I have gotten distilled,water for ironing but the bottles are small.

Any ideas?

Why don't you call the long distance operator, ask for Wal-Mart in Costa Rica (the city you want) and ask them if they carry it?

Agua destilada is available at any farmacia in Costa Rica.

Puedes conseguier agua destilada en cualquier farmacia de Costa Rica.

muchas gracias Sleeprider.

That is what I heard so I won't bother bringing any.

I'd bring a small bottle of your "medicinal liquid" with you just in case.

If the tap water or bottled water is safe to drink, you can use it in your humidifier. Dump and rinse the tank every morning and let it sit dry until the next evening when you can fill it up again. You may have to clean or replace the tank a little more frequently.

ResMed says you should not use tap water in the standard tank, only the optional cleanable tank, but you'd be OK for a few days in a pinch.

Have a nice trip!