Pharmacies across the United States face crowded stores, long lines, and barren shelves as the Omicron variant of coronavirus spreads. Exploding demand for at-home testing kits is compounding with other pandemic pressures to strain many stores.

The highly transmissible Omicron variant hit the country at the heaviest travel season of the year and has left pharmacies struggling as Americans try to travel safely for the holidays. Demand for vaccines and staffing shortages have already put many pharmacies under intense pressure, with some Walgreens (WBA  ) and CVS (CVS  ) locations closing their pharmacy counters early.

Ratcheting pressure from the pandemic is forcing many pharmacies to adapt to continue serving customers. To avoid customers bunching up and spreading the virus quicker, staff at some pharmacies have spread COVID tests throughout the sales floor. Others are restricting sales of tests per customer to try and make existing stock last.

"As the nation experiences a surge in COVID-19 cases coinciding with the holidays, we are seeing unprecedented demand for testing services," a Walgreens spokesperson told the Washington Post. "Due to the incredible demand for at-home rapid testing, we put in effect a four item purchase limit on at-home COVID-19 testing products in our stores and digital properties in an effort to help improve inventory while we continue to work diligently with our supplier partners to best meet customer demands."

The only likely relief to come will be through the eventual waning of the Omicron variant in the US. Staffing shortages from pharmacist burnout are likely to persist until pressures on pharmacy retail ease.

According to some experts, however, a silver lining may come from the fast-acting nature of the Omicron variant itself. It is possible that, as fast as it has spread, Omicron may run its course just as rapidly.