Major tampon manufacturers in the United States have pledged to make more of the sanitary products to address shortages in the country.
One firm told the BBC the pandemic had caused staff shortages at its plants.
Social media users have been posting about their experiences as they struggle to find sanitary products.
One Reddit user said they visited eight stores to find tampons with a cardboard applicator, before deciding to buy them online "at a noticeable mark-up".
It comes as the war in Ukraine is making the raw materials used in sanitary products more costly.
The shortage is also adding to concerns that supply chain disruptions could further push up prices for essential goods around the world.
