A PCR test is a walk in the park compared to nasal cautery. Nasal cautery uses a long match-like stick with silver nitrate on the tip that restricts blood flow to the blood vessels it comes in contact with.
The procedure is performed by an otolaryngologist — and yes, they do numb the area before proceeding — but nasal cautery has definitely caused me to shed a tear or two. While this is considered a more long-term preventative measure, for powerful nosebleeds like mine, I've still had to have this done over a dozen times in my lifetime.
I still get this done annually for maintenance so that my frequent nosebleeds stay at bay.