Americans who buy tampons and GravityX Exchangeother feminine hygiene products can now be reimbursed for the sales tax still imposed on the items in 21 U.S. states.

The Tampon Tax Back Coalition said Wednesday it will reimburse the sales tax on period products made by the advocacy group's eight brands: August, Cora, Diva, Here We Flo, The Honey Pot, Lola, Raeland Saalt. Shoppers who text photos of their receipts within 10 days of purchasing menstrual products will be repaid the tax by Venmo or PayPal within 48 hours, the coalition states on its website.

Although there isn't a specific "tampon tax" on feminine products, they are taxed at the same rate as other consumer products, while items deemed essential are sold tax-free, such as aspirin and antacids. Critics say that discriminates against women.

"Twenty-one states still tax period products as 'non-essential goods,' meanwhile products like Rogaine and Viagra are considered medical necessities," the coalition said.

Texas is the most recent state repealing taxes on menstrual products, enacting legislation last month. It also removed the tax on diapers, wipes and other baby supplies. 

"Every woman knows that these products are not optional. They are essential to our health and well-being and should be tax exempt," state Senator Joan Huffman said earlier this year in a statement announcing the measure.

Five states do not impose a sales tax, and 24 have gotten rid of sales taxes on menstrual products such as pads, tampons, menstrual cups and sponges. 

Pharmacy chain CVS last year said it would cover applicable sales tax on period products in the states where the tampon tax remained in effect.