The purpose of this study is to determine whether melatonin when used as a supplement after surgery improves sleep following total joint arthroplasty

Inclusion Criteria:

1. Patients who undergo unilateral primary total joint arthroplasty
2. Patient willing and able to complete postoperative surveys

Exclusion Criteria:

1. Patients who undergo revision total joint arthroplasty
2. Patients who undergo bilateral total joint arthroplasty
3. Patients currently taking melatonin supplementation
4. Patient has history of substance abuse (drug or alcohol)
5. Patient is a workman's comp patient or patient has current litigation pending
6. Patient has an allergy to melatonin
7. Patient has a history of delirium/psychiatric/depression/on antidepressants
8. Patient has a history of insomnia/ on sleep aid medication
9. Anyone on warfarin
10. Sleep apnea
11. Patient discharged to SNF or rehab
12. Patients who have inflammatory conditions
13. Shift work or night work