Postoperative pain and nausea may diminish a patient's wellbeing, and may also delay rehabilitation, as well as increase the total cost of care and treatment. Opioids are effective drugs for treatment of pain, but with the disadvantage of side effects such as somnolence and nausea. The benefits of various types of non-opioid analgesic in reducing patients' postoperative need for opioids have been well-documented.

One non-opioid prophylaxis documented for various surgery is short-term treatment with corticosteroids. The optimal dose of corticosteroids for peroperative nausea and pain prophylaxis is not well-documented. In our study we will attempt to determine whether the aforementioned benefits of corticosteroids are valid for a group of patients undergoing thyroid surgery.

Hypothesis: Single-dose treatment with dexamethasone provides a better analgesic effect and/or reduced use of opioids than placebo in patients undergoing elective throid surgery. Higher dose of dexamethasone provide better and/or longer-lasting analgesic effects without influencing the side effect profile.

Inclusion Criteria:

• Inpatients scheduled for elective thyroid surgery and parathyroid surgery under general anesthesia.
• Informed consent

Exclusion Criteria:

• Patients who use steroids
• Patients who use antiemetics
• Patients who use opioid analgesics
• Body weight > 100 kg
• BMI > 35