Sebzilla

Sebzilla, otherwise known as Saint Sebastian's Arrow, is a mysterious eye drop like drug taken mostly by Olivia, as she uses it throughout the series. Peter states that it was Egyptian in origin, and it was meant to take people in a higher state of consciousness.

Olivia seemingly uses it to suppress the full ferality and near mindless nature of being an upir, as she is not seen with agonizing hunger like Roman has experienced. Also, her near death seemed to make her mortal enough to develop cancer, though she still retained her superhuman physical abilities.

Sebzilla was bought by Olivia, from Rumanceks, Vince and Lynda, much like drug dealers. Olivia was seen being able to hear hazed and ghostly whispering that Roman said he had also heard, when she did not take the drug, as this was probably a withdrawal symptom of some kind as it stopped the moment she reapplied it.