Exploring other uses of tricyclic antidepressants (TCAs): Efficacy,
safety, and tolerability of using nortriptyline as an analgesic: a
systematic review and meta-analysis
Abstract
Aim: Since the efficacy of some tricyclic antidepressants
(TCAs) in reducing pain has been reported, several studies have
evaluated the analgesic potency of other drugs in this category. This
study aims to accumulate all the data evaluating the efficacy of
nortriptyline in reducing pain. Methods: In accordance with the
PRISMA guideline, clinical trials were imported from PubMed, Web of
Science, and Scopus (until February 2023). Screening stages (based on
pre-defined eligibility criteria) and data extraction were conducted by
two independent researchers. Random- and fixed-effect meta-analysis was
performed to pool the data. Publication bias and study heterogeneity
were assessed. The Cochrane Collaboration tool was utilized to determine
the risk of bias, and the certainty of outcomes was evaluated by the
Grade criteria. Results: Of the initial 648 studies, 14 were
finally imported. Except for one study, all other studies reported that
nortriptyline significantly reduces various types of pain. The pooled
standardized mean difference (95% CI) of reducing pain score as pre-
and post-treatment, compared with placebo, and compared with other
alternative analgesics were -1.20 [-1.48, -0.93], 0.43 [0.23,
0.64], and -0.18 [-0.39, 0.03], respectively. While the most
reported side effects were dry mouth and constipation, all studies
reported that side effects were not serious and were well tolerated.
Outcomes for the effectiveness of nortriptyline and its tolerability got
high certainties. Some studies reported the equality of nortriptyline
with amitriptyline and gabapentin in terms of their analgesic effects.
Conclusion: Using nortriptyline as an analgesic is effective
while being safe and well-tolerated.