In Pfizer’s clinical trials, about 5.6 percent of patients reported an “altered sense of taste,” called dysgeusia in the medical literature. A Pfizer spokesperson assured me that “most events were mild” and “very few patients discontinued study as a result”; the outer packaging of the drug doesn’t mention it at all, and the patient fact sheet breezes past it. But Paxlovid-takers told me it’s absolutely dysgeusting.

The bad taste may come on shortly after people take their first set of pills. (If prescribed Paxlovid, you’re supposed to take three pills, twice daily, for five days.) For a 36-year-old dog walker in Washington, D.C., named sangam ‘alopeke (who styles their name without capital letters), the effect emerged within about an hour of the first dose. Lindsay Wright, a 40-year-old creative director in Winnipeg, Canada, said she noticed it after 90 minutes. Sheila Borkar, a 30-year-old transportation engineer who also lives in Washington, took a pill before bed and woke up to the taste.

“I imagine this is what grapefruit juice mixed with soap would taste like,” Anna Valdez, a nursing professor in Sonoma Valley, California, told me. (We communicated over Twitter direct messages because Valdez had lost her voice from COVID.) “It is horrible and does not go away.”