Many patients experience poor sleep during recovery after total knee arthroplasty (TKA). Disturbed sleep can last weeks to months and may worsen pain, slow healing, and reduce overall quality of life. Few safe, effective, evidence-based options exist to improve sleep during this recovery period. This study aims to determine whether the medications doxepin, either alone or in combination with ramelteon, can improve sleep quality during early recovery after TKA. The investigators will also evaluate whether improved sleep leads to better pain control, knee function, and overall quality of life.