Graff‐Radford 2000.

Study characteristics
Methods	Design: parallel Duration: 8 weeks Assessment: baseline to post‐intervention Country: USA
Participants	Pain condition: post‐herpetic neuralgia Population: adults with post‐herpetic neuralgia Minimum pain intensity: no Inclusion criteria Post‐herpetic neuralgia for at least 6 months Exclusion criteria: NR Total participants randomised: 50 Age in years (mean, SD): 72.9 (10.1) Gender: 22/50 were female Pain duration in months (mean, SD): 33.4 (29.5)
Interventions	Amitriptyline ≤ 200 mg n = 11 TCA Flexible dose dependent upon tolerability Double‐dummy design Amitriptyline ≤ 200 mg + fluphenazine ≤ 3 mg n = 12 Combined intervention: TCA + antipsychotic Flexible doses dependent upon tolerability Fluphenazine ≤ 3 mg n = 13 Antipsychotic Flexible dose dependent upon tolerability Placebo (glycopyrrolate) n = 13 Active placebo Flexible dose dependent upon tolerability Double‐dummy design
Outcomes	Pain intensity Mood Withdrawal
Missing data methods	Completer analysis only
Funding source	Non‐pharmaceutical: "This study was supported by a grant from the National Institute of Health/National Institute of Dental Research (1RO3DE10086‐01)"
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	Low risk	Double‐blind, identical appearing study drugs, double‐dummy design
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Self‐reported outcomes from blinded participants
Incomplete outcome data (attrition bias) All outcomes	Low risk	Completer analysis but only 1 person withdrew Attrition Total: 1/50 (2.0%) Amitriptyline 12.5‐200 mg: 1/12 (8.3%) Amitriptyline 12.5‐200 mg + fluphenazine 1‐3 mg: 0/12 (0.0%) Fluphenazine 1‐3 mg: 0/13 (0.0%) Placebo: 0/13 (0.0%)
Selective reporting (reporting bias)	Unclear risk	No protocol or trial registration found
Other bias	Low risk	No other sources of bias were identified.