PrometheusGeneral

Melatonin and Caffeine: side effects, safety & interactions

Each entry’s own grades, side by side. A grade says how strong the evidence is for one outcome — it does not rank one entry over the other.

Compound or practice

Melatonin

A circadian signal, not a sedative — brilliant for jet lag and shift work at low doses, mediocre as a nightly sleeping pill.

Grade B2 graded outcomesrevised Jul 10, 2026

A structured monograph in Prometheus's bundled library. Its grades are the monograph's own reading of the evidence, not a peer-reviewed review.

Safety

Caffeine: side effects, safety & interactions

Safe for most in moderation; excess causes anxiety, palpitations, and insomnia. Dependence and withdrawal (headache, fat

Grade A0 graded outcomesrevised Jul 10, 2026

Assembled by the app from other entries in this library. It adds no evidence of its own — follow the links to the entries it draws on.

Swap the two

Graded in both

Outcomes are matched by name. Two entries can describe the same outcome in different words, so one listed further down may still be graded in the other.

No outcome has the same name in both entries. They may still overlap under different wording — read the two lists below.

Graded only in Melatonin

  • Jet lag / circadian shift Moderate effectEvidence grade B
  • Sleep onset (insomnia) Small effectEvidence grade B

Graded only in Caffeine: side effects, safety & interactions

None — every outcome it grades is graded in both.

Conditions

Only in Melatonin

Only in Caffeine: side effects, safety & interactions

None.

What each entry says about the other

  • Caffeine: side effects, safety & interactions’s entry · Watch with: Opposing circadian signals — the afternoon cutoff protects the melatonin window.

Both columns are read from the entries as they stand in this library. A comparison is not advice to take either one, and it is no substitute for a clinician who knows the person.