My Way Home - S5-E7
Character mistake: Early in the episode, Keith pages JD from home to the hospital. When JD arrives, he asks Keith what's the big emergency and Keith asks if he wants the patient to be prescribed unfractionated or low molecular weight heparin. JD gets angry and says that they're the exact same thing. This is in fact completely incorrect. Low molecular weight heparin is made from fragments of unfractionated heparin. They have different effects in their metabolism, half life and dose monitoring (unfractionated needs a blood test, low molecular weight doesn't). The choice between unfractionated and LMWH is an important clinical decision and should not be dismissed as "the exact same thing".
Answer: No, it was a fake, they used a stamp.
It is real.