Does Melatonin help stress? (Grade B evidence)
Melatonin shows a Grade B benefit for stress — moderate-certainty evidence from randomised trials, especially in adults undergoing surgery. Typical studied doses are varies; given before surgery in the trials.
Bottom line. Melatonin shows a Grade B benefit for stress — moderate-certainty evidence from randomised trials, especially in adults undergoing surgery. Typical studied doses are varies; given before surgery in the trials. [1 RCT]
- Direction
- benefit
- Magnitude
- Cochrane review of 27 RCTs (2319 participants): melatonin reduced preoperative anxiety versus placebo, with effects broadly comparable to benzodiazepines such as midazolam in the trials that compared them. Evidence for postoperative anxiety was less certain. This is an acute, perioperative-anxiety context, not general everyday stress.
- Grade
- B
- Certainty
- moderate
- Clinical meaning
- small but potentially useful
- Who it applies to
- adults undergoing surgery
- Dose / form studied
- Safety
- uncertain_with_ssri
- The one limitation
- Sample sizes are small in most included trials; effect sizes may shrink with larger studies.
Reviewed · Evidence last changed · Claim clm_ec_b7-mel-stress v1
⚠ Safety in context
- uncertainwith SSRI: Melatonin with an SSRI: possible additive sedation; evidence is thin. full interaction →
Grade B / moderate: probably helps, and new studies are unlikely to reverse this — but could shrink the effect size.
Who it works for
Best-studied in adults undergoing surgery. Effective doses cluster around varies; given before surgery in the trials.
Evidence
| Study | Design | Cite |
|---|---|---|
| Melatonin for preoperative and postoperative anxiety in adults. | peer-reviewed | PMID:33319916 |
Why this grade
Reasoning trace
Grade B at moderate certainty. The grade reflects the direction and size of the effect across the 1 publishable source above; certainty reflects heterogeneity, sample sizes, and design quality. What would move it upward: additional well-powered RCTs in the target population that replicate the effect at similar doses. What would move it down: a large null trial, discovery of publication bias, or a retraction of a keystone study.
Dose & form
Studied intake: varies; given before surgery in the trials.
How it stacks up for stress
- Melatonin vs L-Theanine for stress — L-Theanine Grade C
- Melatonin vs Ashwagandha for stress — Ashwagandha Grade C
- Melatonin vs Magnesium for stress — Magnesium Grade C
- Melatonin vs Rhodiola for stress — Rhodiola Grade C
- All interventions graded for stress →
Grade history
No grade changes yet. Initial grade assigned; re-reviewed on every 12 months (Grade A/B) — next review by . Methodology v1.
Re-review cadence: every 12 months (Grade A/B) · next scheduled by · methodology v1.
Frequently asked
How long does Melatonin take to work for stress?
Trials of Melatonin for stress typically report effects within 2–4 weeks, though individual response varies. Studies rarely find benefit inside 1 week for chronic outcomes.
What dose was used in studies of Melatonin for stress?
Studied doses for Melatonin in stress trials cluster around varies; given before surgery in the trials. See the dose block for the specific range and how it varies by form.
Does Melatonin work for stress if I'm not deficient?
The effect concentrates in adults undergoing surgery. If your baseline is normal, expect a smaller effect than the trial averages.
Melatonin or the next-best alternative for stress?
See the compare block above for the head-to-head with the most-cited alternative. Grade + certainty differences matter more than any single trial.
Related
What this is — and is not
- Evidence description
- Cochrane review of 27 RCTs (2319 participants): melatonin reduced preoperative anxiety versus placebo, with effects broadly comparable to benzodiazepines such as midazolam in the trials that compared them. Evidence for postoperative anxiety was less certain. This is an acute, perioperative-anxiety context, not general everyday stress.
- Substrate's interpretation
- Grade B at moderate certainty — the direction and size the studies converge on, as our reading of the corpus.
- Discuss with a clinician
- If you're on medication or have a condition that changes the calculus, bring the interaction & population blocks above to your pharmacist or prescriber before deciding.
- Individualized medical advice
- Not provided here or on any Substrate surface (API, agent tool, embed) — see YMYL policy.
Cite this page
Reuse under CC-BY 4.0 with attribution to evidencebased.info.
Plain-text citation
Substrate. Does Melatonin help stress? (Grade B). https://evidencebased.info/interventions/melatonin/stress. Updated 2026-07-16.
BibTeX
@misc{substrate_tionsmelatoninstress,
author = {Substrate editorial},
title = {Does Melatonin help stress?},
year = {2026},
url = {https://evidencebased.info/interventions/melatonin/stress},
note = {Grade B, evidencebased.info}
}Found something wrong on this page? Report an error →