Neuropathic pain Nervous System Diseases Polyneuropathy in diseases classified elsewhere
Conditions
Interventions
1. Morphine-nortryptyline combination
2. Morphine
3. Nortriptyline
As per a double-dummy, balanced Latin Square design, trial medications are administered orally in three different treatment periods.
Sponsors
Queen's University (Canada)
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: 1. Neuropathic pain 2. Daily moderate (greater than or equal to 4/10) pain for at least 3 months 3. Adults aged 18 to 89 years, either sex 4. Liver function tests: alanine aminotransferase (ALT), aspartate aminotransferase (AST) less than 1.2 times upper limit of normal 5. Creatinine less than 1.5 times upper limit of normal 6. Negative serum beta-human chorionic gonadotrophin (B-HCG) for women of childbearing potential 7. Adequate birth control for all women of child-bearing potential 8. Sufficient cognitive function, visual acuity and English language skills to complete questionnaires and communicate verbally with the nursing staff to permit titration of the study drugs
Exclusion criteria
Exclusion criteria: 1. Painful condition as severe as, but distinct from presenting neuropathic pain 2. Pregnancy or lactation 3. End-stage kidney or liver disease 4. Moderate to severe heart disease (myocardial infarction [MI] within preceding year, unstable angina, cardiac conduction defect or congestive heart failure) 5. Cardiovascular autonomic neuropathy 6. Postural hypotension greater than 20 mmHg on initial assessment 7. Males with urinary symptoms attributable to benign prostatic hypertrophy 8. Patients who live alone and cannot assure daily contact with a friend, family member or caregiver 9. Angle-closure glaucoma 10. Ongoing administration of monoamine oxidase inhibitors, serotonin-specific reuptake inhibitors, serotonin-norepinephrine inhibitors 11. Any serious psychiatric disorder as diagnosed by a psychiatrist (including bipolar disorder) 12. Seizure disorder 13. Ongoing administration of anticonvulsants which induce cytochrome P450 enzymes (e.g. carbamazepine, oxcarbazepine, barbiturates and phenytoin) as well as rifampin 14. Hypersensitivity to, or previous intolerability of, any of the study medications 15. History of significant abuse of illicit drugs, prescription drugs or alcohol
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Daily pain intensity. Patient follow-up for primary and secondary outcomes were recorded during treatment at maximal tolerated dose (i.e. day 25 - 31) for each treatment period. | — |
Secondary
| Measure | Time frame |
|---|---|
| 1. Global pain relief, measures of sedation, constipation, other side effects and maximal tolerated drug doses 2. Short form McGill Pain Questionnaire-2 3. Brief Pain Inventory 4. Beck Depression Inventory 5. 36-item short form health survey (SF-36) 6. Blinding questionnaires 7. Acetaminophen consumption 8. Serum drug levels Daily pain intensity. Patient follow-up for primary and secondary outcomes were recorded during treatment at maximal tolerated dose (i.e. day 25 - 31) for each treatment period. | — |
Countries
Canada
Outcome results
None listed