Effects of opioid analgesics on driving ability of pain patients.

1. Age: 30 to 65;

2. Body weight within 16-35 according to body mass index (BMI);

3. Vision normal or corrected to normal;

4. Valid driver’s license for passenger cars;

5. Kilometres travelled per year: at least 2.000 km per year during preceding 12 month;

6. Driving on a regular basis: at least once per week;

7. Ability to drive a passenger car with manual transmission;

8. Treatment for at least four weeks with:

A. Transdermal Fentanyl (e.g. Durogesic Smat®) = 12 µg/h, or;

B. Transdermal Buprenorphine (e.g. Transtec®) = 10µg/h, or;

C. Retarded Oxycodone (e.g. Oxygesic®) = 10 mg/day, or;

D. Retarded Oxycodone combined with Naloxone (z.B. Targin ®) = 10 mg/day, or;

E. Retarded Hydromorphone (z.B. Palladon®, Jurnista®) = 4 mg /day, or;

F. Retarded Morphine (z.B. MST®) = 20 mg/day, or;

G. Retarded Tramadol (z.B. Tramal long®) = 100 mg/day, or;

H. Retarded Tilidin combined with Naloxone (z.B. Valoron N ®) = 100 mg/day.

9. No dose change within the preceding 14 days;

10. Co-medication with NSAID and/or anticonvulsants and/or antidepressants on a stable dose within the preceding 14 days.

1. Subjects who fail to meet any of the inclusion criteria;

2. Persons who are imprisoned or are detained in a health mental institution by court or official order;

3. Malignant disease;

4. Severe disabilities that are expected to interfere with computerized testing or car driving;

5. Expected inability to drive the experimental car safely or to complete computerized testing or endangerment of being overstrained during the driving test or during computerized testing according to the estimation of the physician accomplishing the medical check up;

6. Psychological or psychiatric disorders or severe physical disorders (history or current evidence of severe physical or mental disorders, serious gastrointestinal, hepatic, renal, cardiovascular or neurological disorders or severe allergies) that may interfere with participation in computerized testing or driving test;

7. Subjects with alcohol or drug abuse or dependency;

8. Unwillingness or inability to abstain from consumption of alcohol, psychoactive medication or drugs within 24 hours prior to the assessment day (urine drug screening, alcohol breath analyzer);

9. Excessive drinkers (more than 28 glasses of alcohol containing beverages per week);

10. Inability or unwillingness to abstain from smoking for the duration of the driving test or the computer based test;

11. Regular intake of Benzodiazepines (= 4 times per week);

12. Intake of Benzodiazepines within 2 days before assessment days;

13. Regular intake of barbiturates (> 3 times per week) as well as intake of barbiturates within 2 days before the assessment days;

14. Daily intake of antidepressants in higher dosage (Amitryptilin > 75mg, Doxepin > 75mg, Imipramin > 75mg, Trazodon > 100mg, Sertralin > 50mg, Fluoxetin > 20mg, Fluvoxamin >75mg, Duloxetin > 120mg, Venlafaxin > 225mg, Citalopram > 10mg);

15. Daily intake of anticonvulsant in higher dosage (Carbamazepin > 1200mg, Oxcarbazepin >1800mg, Gabapentin >2400mg, Pregabalin >600mg);

16. Intake of MAO inhibitors;

17. Regular intake of un-retarded opioids (= 7 times per week) or intake of un-retarded opioids within 2 days prior to assessment and on the assessment days;

18. Regular intake of antihistamines;

19. Inability to communicate meaningfully with the study staff (insufficient language skills);

20. Participation in another study within 30 days before enrolment to this study.