Opioid study reveals how painkillers affect mood before surgery

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: \- Health status ASA1 (American Society of Anesthesiologists physical status) or ASA2 as categorised by a medical doctor at the hospital based on medical history, physical examination, laboratory test etc. unrelated to the current study. ASA1 and ASA2 (ASA1 is defined as "Healthy, non-smoking, no or minimal alcohol use" and ASA2 is defined as "Mild diseases only without substantive functional limitations). Being eligible for day surgery means participants are overtly healthy as determined by clinical staff. * The participant is considered as eligible for the use of fentanyl, morphine and oxycodone by a medical doctor at the hospital, based on an overall assessment of the psychiatric and somatic condition, used medical drugs, regarding possible interactions and contraindications for the use of the study medicaments. * Body weight and body mass index (BMI) within the range 18-35 kg/m2 (inclusive). * Capable of giving signed informed consent as which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in this protocol. * Having good verbal communication skills in Norwegian. * Patients undergoing planned day surgery with general anesthesia (outpatient sample). * Orthopedic, rectal, gynecological, hand and foot surgery, and minor vascular procedures. * Inpatients undergoing planned gynecological and orthopedic surgery. * Hysterectomy, laparoscopic ovariectomy, lumbal herniotomy and other related procedures. * Minor gastrointestinal surgery Exclusion Criteria: 1. Known allergic reactions to morphine, oxycodone,or fentanyl. Known allergic reactions to any of the incredients described in the SPC, pt 6.1. 2. Severe chronic obstructive lung disease, 3. Cor pulmonale, 4. Severe bronchial asthma, 5. Severe respiratory failure with hypoxemia and hypercapnia 6. Moderate to severe hepatic impairment, 7. Moderate to severe kidney failure 8. Acute abdomen 9. Increased brain pressure 10. Head trauma 11. Use of MAO blockers in the last two weeks 12. Hypovolemia 13. Hypotension 14. Myasthenia gravis 15. Any other health status not corresponding to ASA1 or ASA2. This includes patients with severe disease burden, major psychiatric disorders that could interfere with the procedures and communication. 16. Pregnancy. Women of childbearing potential defined as all premenopausal female (a postmenopausal state is defined as no menses for 12 months without an alternative medical cause) will be asked if they are pregnant. 17. Breastfeeding women. 18. Illegal drugs use like opioids, cocaine and amphetamine