Max 1988.

Study characteristics
Methods	Design: cross‐over Duration: each cross‐over period was 6 weeks Assessment: baseline and post‐cross‐over period Country: USA
Participants	Pain condition: post‐herpetic neuralgia Population: adults with post‐herpetic neuralgia Minimum pain intensity: no Inclusion criteria Daily pain, persisting at least 3 months after a segmental herpes zoster eruption Exclusion criteria Another type of pain as severe Depression Total participants randomised: 58 Age in years (median, range): 72 (25‐86) Gender: 27/58 were female Pain duration in months (median, range): 19 months (3 months‐25 years)
Interventions	Placebo Inert ‐ lactose "Placebo (PLAC) is given only during the first period, because both amitriptyline (AMI) and lorazepam (LOR) have prominent side effects. We predicted that patients given placebo following one of those drugs would immediately recognize this inert treatment. The design permitted a comparison of AMI, LOR, and PLAC during the first treatment period." Amitriptyline 12.5‐150 mg TCA Forced titration to maximum tolerable dose in first 3 weeks, then held at that dose for final 3 weeks Lorazepam 0.5‐6 mg Benzodiazepine Forced titration to maximum tolerable dose in first 3 weeks, then held at that dose for final 3 weeks
Outcomes	AEs
Missing data methods	Unclear
Funding source	Non‐pharmaceutical: from the Neurobiology and Anaesthesiology Branch, National Institute of Dental Research (Drs Max, Gracely, Smoller, and Dubner). and the Nursing Department, Clinical Center (Ma. Schnfer and Me. Culnane), National Institutes of Health, Bethesda, MD
Conflicts of interest	NR
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Randomisation methods not specified
Allocation concealment (selection bias)	Unclear risk	Allocation procedures not specified
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Says double‐blind but no information about this was given
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Self‐reported outcomes from participants, but unsure of blinding procedures
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No information regarding missing data reported. 41 completed both of the treatment periods for their group, but authors report data on 58
Selective reporting (reporting bias)	Unclear risk	No protocol or trial registration found
Other bias	Low risk	No other sources of bias identified