Where PRP hurts most, and what the days afterward are like

WHAT IT FEELS LIKE

It is not the needle people remember. It is the two or three days afterward, and how much those days differ depending on what was injected.

Why the soreness happens at all

PRP works by provoking a controlled inflammatory response — that is the mechanism, not a side effect of it. A treatment that produced no reaction would be a treatment that did not signal anything. So post-injection soreness is expected, informative, and the part of the consent that is most often glossed over.

It gets worse before it gets better, and that is the treatment — but knowing that in advance is the difference between a normal week and a frightening one.

By site, honestly

• Tendon, and especially an enthesis. The most uncomfortable of them. Injecting into a tightly bound structure with limited compliance produces real pressure pain during the injection and a pronounced ache for two to four days. Gluteal and patellar tendons are typically the ones people rate highest.
• Plantar fascia. Small volume into dense tissue on a weight-bearing surface. Brief and sharp, then a few days where the first steps are worse than usual before they are better. The first step out of bed is the diagnosis, and it is also the thing that tells you the treatment is working.
• Large joints. Knee and hip are generally the easiest. The capsule accommodates volume, the injection itself is brief, and the ache that follows is a fullness rather than a sharpness. Foot and ankle work sits between the two.
• Spine. Different again, because the discomfort is mostly positional afterward rather than at the site. We do not inject a level until a block has told us it is the one.
• The blood draw. Worth saying because people brace for it and it is the least of the day.

The three days, in order

Day zero is usually the easiest — local anesthetic is still working and people frequently leave feeling better than they expected. Days one and two are the peak, and they are the days to clear the calendar for. By day four most people are back to their baseline discomfort, and the actual benefit begins arriving over the following weeks.

What we ask you not to do in that window is take an anti-inflammatory to blunt it. That is the one instruction people break, and it works directly against the mechanism you have paid for. Acetaminophen, ice, and knowing it is coming are the plan.

What is not normal

Expected soreness is proportionate, local, and improving by day three or four. What is not expected: pain that escalates after day three, fever, spreading redness, or a joint that becomes hot and increasingly swollen. Those are the calls to make rather than wait out. The expected, the uncommon, and the three that warrant a call are listed separately and deliberately short.

Infection after an autologous injection performed under sterile conditions is rare. Rare is not never, which is why the list exists and why we would rather hear from you.