The primary objective of this study is to evaluate the analgesic efficacy of Dexmedetomidine Transdermal System (DMTS), compared with placebo, in participants following abdominoplasty.

This is a randomized, double-blind, placebo-controlled, one-time application study of DMTS or matching placebo over a 4-day treatment period.

Eligible subjects will be randomized in 1:1 ratio to receive DMTS or matching placebo. Subjects will reside at the clinical study unit for up to a total of 7 days. The surgical procedure, the intraoperative anesthesia, and the medication used for infiltration of the wound for local anesthesia before the last stitch will be standardized. During the postoperative period in the clinical study unit, recovery procedures will be standardized.

Inclusion Criteria:

1. Voluntarily provide written informed consent.

2. Male or female, ≥ 18 years of age.

3. Scheduled to undergo a full abdominoplasty (including repair of small incidental abdominal hernias but not including liposuction).

4. Have a physical status classification of 1 or 2 per the American Society of Anesthesiology.

5. Female subjects are eligible only if all the following apply:

   1. Not pregnant, not lactating, and not planning to become pregnant during the study or for 1 menstrual cycle thereafter
   2. Surgically sterile; or at least 2 years postmenopausal; or have a monogamous partner who is surgically sterile; or have a same gender sex partner; or is using double-barrier contraception; or practicing abstinence; or using an insertable, injectable, transdermal, or combination oral contraceptive for 3 months prior to the study, during the study, and for 1 month following the study

6. Male subjects with female sex partners of childbearing potential must be surgically sterile or commit to use a reliable method of birth control during the study and for 1 month following the study.

7. Have a body weight > 58 kg and a BMI of 20 to 38 kg/m2, inclusive.

8. Able to understand the study procedures, comply with all study procedures, and agree to participate in the study program for its full duration.

Exclusion Criteria:

1. Known sensitivity to dexmedetomidine or any excipient in the DMTS/placebo or to any peri- or postoperative medication whose use is required in this study.
2. Skin abnormality (eg, scar, tattoo) or unhealthy skin condition (eg, burns, wounds) at the DMTS/matching placebo system application site, according to examination by the investigator at screening or admission to the clinic prior to surgery.
3. Clinically significant abnormal clinical laboratory test value.
4. History of deep vein thrombosis or factor V Leiden deficiency.
5. History of or positive test results for the human immunodeficiency virus (HIV), hepatitis B, or hepatitis C.
6. History or clinical manifestations of: a significant renal, hepatic, cardiovascular, metabolic, neurologic, or psychiatric condition; congestive heart failure, peptic ulcer, gastrointestinal bleeding, or other condition that may preclude participation in the study.
7. History of physician-diagnosed migraine, frequent non-vascular headaches (> 5 per month), seizures, or are currently taking anticonvulsants.
8. Have another painful physical condition that may confound the assessments of postoperative pain.
9. History of syncope or other syncopal attacks.
10. Present and/or significant history of postural hypotension (determined through examination by the investigator or designee), or history of severe dizziness or fainting on standing in the opinion of the investigator.
11. Evidence of a clinically significant 12-lead ECG abnormality.
12. Supine heart rate < 60 or > 100 bpm, systolic blood pressure (BP) < 90 or > 140 mmHg, or diastolic BP < 60 or > 90 mmHg, when measured in triplicate: after being supine for at least 5 minutes; after sitting for at least 2 minutes; and after standing for at least 2 minutes.
13. History of alcohol abuse or prescription/illicit drug abuse within the previous 5 years.
14. Positive results on the urine drug screen or alcohol breath test indicative of drugs of abuse or alcohol use at screening and/or clinic check-in.
15. Receiving or have received opioid therapy chronically for > 2 weeks within the month prior to dosing of the study drug.
16. Receiving concurrent therapy that can interfere with the evaluation of efficacy or safety, such as any drug that in the investigator's opinion may exert significant analgesic properties or act synergistically with dexmedetomidine.
17. Used of any natural health products (including chaparral, comfrey, germander, jin bu huan, kava, pennyroyal, skullcap, St. John's wort, or valerian, and excluding vitamins or mineral supplements) within 14 days prior to study drug administration and throughout the study, unless in the opinion of the investigator or designee, the product will not interfere with the study procedures or data integrity, or compromise the safety of the subject.
18. Had symptoms of an upper respiratory tract infection within 14 days prior to dosing of the study drug.
19. Utilized oral or injectable corticosteroids within 14 days prior to dosing of the study drug (intranasal and topical corticosteroid use during this time period is allowed).
20. Received any investigational product within 30 days prior to dosing of the study drug.
21. Received DMTS in a previous clinical trial.
22. Sensitivity to opioids, nonsteroidal anti-inflammatory drugs, or antibiotics.
23. In the opinion of the investigator or designee, is considered unsuitable for study entry and/or is unlikely to comply with the study protocol for any reason.

The sponsor, the investigator, personnel at the clinical study unit who are directly involved with monitoring and/or performing study procedures and assessments, and the subjects will be blinded to treatment assignment.