Rheo™ is HSA and FSA Eligible

enjoy savings of 30-40% on oral hydration


Oral Pouch Solutions has partnered with Flex to allow qualified customers to use their Health Savings Account (HSA) or Flexible Spending Account (FSA). This means you may be able to use your HSA or FSA debit card to buy any eligible Rheo™ pouch with pre-tax dollars, resulting in net savings of 30-40%.

How to Checkout Using HSA/FSA Card

  • Add Products

    To use your HSA or FSA debit card, add products to your cart as usual.

  • Checkout

    At checkout, select “Flex | Pay with HSA/FSA” as your payment option, enter your HSA or FSA debit card, and complete your checkout as usual.

  • Having Trouble

    If you don’t see “Flex | Pay with HSA/FSA,” you may be in Shop Pay. Select “checkout as guest” to view more payment options.

Within 24 hours of your purchase, Flex will send you an email that includes your Letter of Medical Necessity and an itemized receipt. Be sure to keep these documents for your records in case your HSA/FSA provider or the IRS requests additional verification.

For more details, take a look at the FAQ section below.

Frequently Asked Questions about FSA

If you don’t have your HSA or FSA card handy, still select “Flex | Pay with HSA/FSA” as your payment method. Enter your credit card information and Flex will email you an itemized receipt to submit for reimbursement.

The key here is to make sure you are logged out of ShopPay. One of the easiest ways to do this is to go through checkout in an incognito window.

HSA/FSA cards are debit cards, and the most common reason for declines is insufficient funds. Reach out to your HSA/FSA administrator to confirm your balance.

Please forward us the request from your FSA, and we will work with the Flex team to issue you a new receipt.

Please check your spam folder, as sometimes emails from notifications@withflex.com may be automatically filtered as spam by some email service providers. If you still can’t find it, please email support@withflex.com and let them know the email address associated with your order.

No, unfortunately, this isn’t a supported feature right now. If there are insufficient funds in a single HSA or FSA account, you can instead enter a credit card on the Flex checkout page. You will receive an itemized receipt and/or Letter of Medical Necessity from Flex, which you can submit for reimbursement.

Thanks for reaching out, and apologies for the discrepancy. We’ll review the charges and get back to you with details of the likely refund shortly.

Sales tax for eligible items is also covered by HSA/FSA funds. If the customer has a split cart, the tax will be divided among the cards based on the items.

Dentist Formulated · Long Lasting Relief · All Natural

Amazing product

Flavor : Mint

“This product has been a game changer. I highly recommend it if you’re suffering from dry mouth from a medication.”

J. Michael Atwater, PhD · Reviewed in the United States on December 2, 2025

Best Dry Mouth Relief I’ve Found

Flavor Name: Mint

“Really impressed with these. They work fast, taste fresh, and don’t leave any weird aftertaste. The relief actually lasts, and the pouches are super convenient to use anywhere. I’ve tried a lot of dry-mouth products, and this is easily one of the best.”

AJ Norris · Reviewed in the United States on December 2, 2025

Relieves dry mouth for extended period of time.

Flavor Name: Citrus · Verified Purchase

“This product is a game changer! I have tried lozenges, mouthwashes, xylimelts, and gums…..this is the best tasting and lasts the longest! So discrete and can use on the go. These will always be on me to use as my dry mouth is bothersome. I highly recommend you give these a try!!! Did I mention they taste amazing…”

Courtney L. Russell · Reviewed in the United States on December 22, 2025

Remedy for dry mouth.

Flavor Name: Citrus

“Family member who uses medications that cause dry mouth has experienced relief with the use of these oral pouches.”

Sara · Reviewed in the United States on December 3, 2025