For elective abdominal surgery preoperative administration of 8 mg dexamethasone reduces the incidents of postoperative nausea and vomiting (PONV). Whether preoperative administration of 8 mg dexamethasone reduces PONV for patients having acute abdominal surgery has not been established. The investigators wish to see if preoperative administration of 8 mg dexamethasone minimum 30 minutes prior to a diagnostic laparoscopy for suspected appendicitis will reduce the incidents of PONV by 50%. Of secondary interest the investigators want to see if 8 mg dexamethasone preoperative can reduce pain, reduce opioid consumption, postoperative fatigue, duration of time until resumption of work and resumption of normal daily activities, and enhanced the quality of recovery.

Eligible patients undergoing a diagnostic laparoscopy for suspected appendicitis will be randomized to receive placebo or 8 mg dexamethasone intravenously minimum 30 minutes prior to the operation.

Randomization will be done by envelope randomization. We would expect that 60% of the patients would experience postoperative nausea or vomiting (PONV) during the first 24-32 hours postoperatively. To show a 50% reduction in the incidents of PONV during the first 24-32 hours postoperatively (with a power of 80%, a significant level of 5% and a loss to follow up of 20%) we need 60 patients in each arm. So a total of 120 patients are to be randomized 1:1.

Both sites use paper Case Report Forms (CRF). The trial will be monitored by the regional GCP (Good Clinical Practice) unit and adhere to GCP guidelines.

Patients are assessed by self reporting questionnaires preoperatively and postoperatively after 2-10 hours, 8-16 hours, 24-32 hours, on postoperative day (POD) 2, POD 3, POD 7, POD 14 and POD 30.

Preoperative anxiety recorded by a VAS scale, Pain Catastrophizing Scale and Hospital anxiety and depression scale are recorded by the preoperative questionnaire.

A short telephone interview will be done during the first postoperative day regarding duration of abdominal pain prior to admission, social status regarding children and whether they living with another adult, smoking status, use of sleep medication or use of psychopharmacy a minimum of 7 days prior to the operation, physical level of normal daily activities, physical level of work, educational and occupational background.

Other demographics such as height, weight, ASA class, age, last CRP prior to the operation, duration of the operation, date and time of admission, date and time of discharge are registered through the electronic patient record files. Pathology of any removed tissue are registered trough the pathology report.

Diagnosis at the operation, preformed procedure, whether the preforming surgeon was supervised, number of identical procedures preformed previous by the surgeon or the surgeons supervisor (if supervised) will be recorded in the patients CRF by the preforming surgeon.

Pre-, intra- and post-operative pain medication, antiemetics and antibiotics are recorded through the electronic patient medication files.

Postoperative complications and adverse events are recorded through the electronic patient record files and by telephone interview.

To ensure a high completion rate, patients are contacted by telephone at each registration time postoperatively.

Parametric or non-parametric statistical analysis will be used when appropriate.

Inclusion Criteria:

• Scheduled for a diagnostic laparoscopy for suspected appendicitis
• ASA clas I-III

Exclusion Criteria:

• Known inflammatory bowel disease
• Known autoimmune disease.
• Chronic pain patient.
• Pregnant or breastfeeding.
• In treatment with systemic corticoid steroids or immune-depressants.
• Known glaucoma.
• Known ocular herpes simplex.
• Vaccination within 14 days prior to inclusion.
• Known cushing's disease.
• Known myasthenia gravis.
• Presumably poor compliance with study protocol.