In addition to arm soreness and a little malaise, some people are reporting an unusual side effect following their COVID-19 vaccinations: an intense metallic taste that can last for days. The experience is "like having nickels in your mouth," said John Howard, 45, of Columbia, South Carolina. The sensation came on within minutes of receiving his first dose of the Pfizer COVID-19 vaccination this past week. He tried to get rid of it with coffee, then mouthwash. Twenty-four hours later, the metal taste remained.