Lactium

Alpha-s1 casein hydrolysate · Alpha-casozepine · Casein hydrolysate

Snapshot

Indications	Contraindications
Sleep disturbance^{1, 2} Sleep efficiency^{1, 2} Wake after sleep onset^{1, 2} Stress-related acne³	Milk allergy⁴ Pregnancy or nursing⁴

Lactium is the trade name for alpha-s1 casein hydrolysate, a milk-derived peptide preparation that includes the decapeptide alpha-casozepine. It is taken for sleep disturbance and for stress-related complaints, mainly by adults with mild to moderate sleep problems. In acne, stress reduction with Lactium has been measured through serum cortisol and perceived stress scores³.

Sleep evidence is mixed. In a crossover trial, sleep diary and actigraphy measures improved with Lactium, while questionnaire scales and polysomnography did not differ from placebo¹. A multi-ingredient complex containing Lactium did not beat placebo on sleep quality in mild insomnia, amid a marked placebo response⁵. In a 2024 double-blind trial of a Lactium and L-theanine combination, stool analysis showed higher Blautia and Ruminococcus, a gut microbiota link to sleep that no further trial has tested. Products are mostly capsules, with some powders, usually in multi-ingredient stress and sleep formulas; 1387 products list Lactium (see Form comparison).

The most consequential caution is milk allergy, because the peptides derive from casein; the sampled United States (US) product labels carry a milk-protein warning⁴. A few US labels ask people taking thyroid hormones, or with gastrointestinal ulcers, to consult a practitioner before use⁴.

Last updated October 16, 2026. Read how we make monographs.

In the full monograph

38 sources, 31 studies

When to useThe situations practitioners use it for, each with the reason and the study behind it.
SafetyWho should avoid it, who needs extra care, and the side effects reported in studies.
InteractionsThe medicines and supplements it interacts with, the effect of each, and what labeling says to watch.
Protocol notesThe doses used in studies, how and when they were taken, and how the forms on the market compare.
How it worksWhat it is and how it works in the body, in plain terms.
Published studiesThe studies behind each use, popular claims checked against them, and trials still under way.
Word of mouthWhat patients and practitioners report online, kept separate from the clinical evidence.
Clinical perspectiveA closing read of where the evidence is solid, where it is thin, and what has not been studied.

Snapshot

In the full monograph

Sources