Police were called to an Allentown apartment at about 1:40 a.m. Saturday after a reported domestic dispute.
The Lehigh County coroner's office said 31-year-old Lauren Wolstenholme was pronounced dead two hours later.
The manner of death has been ruled homicide but the cause of death is pending an autopsy Monday.
Police said a 31-year-old man armed with a knife was taken into custody after he was hit by a stun gun.
Investigators said he had apparently taken drugs and was taken to St. Luke's Hospital in Allentown; he was to arraigned when medically fit.