Some supermarket shelves are being emptied as shoppers stockpile amid fears the coronavirus outbreak could force stores to limit their supplies.
People have begun to stockpile items such as hand sanitiser and pasta due to the spread of the virus, despite authorities insisting it would not be necessary to do so.
Some pharmacies have run out of ibuprofen and vitamins.
The stockpiling has prompted some to take to the Facebook Marketplace to flog essentials for inflated prices, with one seller in Australia reportedly advertising a 24-pack of toilet roll for $24,000 (£12,400), Australian broadcaster 7news reported.
Others have reportedly taken to trade website Gumtree to offer a 34 pack of loo roll for a slightly more moderate $20 (£10.30).
Sharon Reilly photographed a shop in Massachusetts, United States, noting that toilet paper stocks were running low while “all the bleach was gone too”.
She told the PA news agency: “It did not make me feel like I needed to stockpile. It made me sad that people are clearly scared.”
Meanwhile Franziska Heintel shared photos of empty supermarket shelves in Berlin.
“I’m not sure if it’s an accurate representation and I don’t want to make people panic even more,” she said.
“I was just super shocked and surprised to see this when I was just doing some regular shopping.”
According to MailOnline, sales of hand sanitiser in British supermarkets hiked from 468,433 in February 2019 to 1,156,102 in the four weeks to February 23 2020.
This comes after Public Health England advised Brits to wash their hands for 20 seconds to help contain the deadly illness.
However, on Tuesday the UK Government’s chief scientific adviser Sir Patrick Vallance said there was no need for Britons to be panic buying.
“I think the advice is that there is absolutely no reason to be doing any panic buying of any sort or going out and keeping large supplies of things,” he told journalists.
“Clearly there will need to be measures in cases of household quarantine for making sure food is in the right place at the right time.
“We imagine that could be a rolling case of household quarantine if that measure becomes necessary, and clearly things will need to be in place for care homes and so on if that decision is made.”
His comments came after Ocado warned that more people than usual are “placing particularly large orders”.