Topical vitamin K for bruising: timing changed the trial result

What the source establishes

Twenty-two patients entered a blinded split-face study. One group applied vitamin K cream or vehicle before laser treatment, while the other applied them afterward. [1]

Pretreatment did not significantly prevent bruising. Application after laser treatment produced lower bruising-severity scores than vehicle, especially early in follow-up. [1]

What it does not establish

Each timing group contained only eleven people. The study tested a topical formulation after a controlled procedure, not oral supplements or bruises of unknown cause. Funding and conflicts were not established from the abstract; spontaneous bruising cannot be diagnosed from this experiment. [1]

A hypothetical distinction

Imagine a treatment helps an existing mark fade but does not prevent it from forming. Prevention and recovery are distinct questions even when the same preparation is used.

Evidence summary — Topical vitamin K for bruising
Detail	Interpretation
Before procedure	No preventive signal
After procedure	Severity signal
Oral supplementation	Not tested

Topical vitamin K for bruising: timing changed the trial result — original article outline diagram — Original editorial diagram of this article’s sections; no product photograph or clinical finding is depicted.

Sources for this article

The effects of topical vitamin K on bruising after laser treatment - PubMed
Source consulted: 2026-09-19. This is a reference resource, not a claim that we conducted the studies or tested a product.