How can you distinguish dandruff from lice eggs on the head? - briefly
Dandruff consists of loose, white powdery flakes that brush away easily, whereas lice nits are oval, yellow‑brown and firmly cemented to the hair shaft close to the scalp. A fine‑tooth comb under bright light will reveal the immobile nits, while flakes fall off with a gentle pull.
How can you distinguish dandruff from lice eggs on the head? - in detail
Scalp flakes and lice nits differ in size, shape, attachment, and texture. Dandruff consists of loose, powder‑like particles that drift from the scalp when brushed or shaken. Nits are oval, rigid structures about 0.8 mm long, firmly glued to each hair shaft near the scalp, usually within a half‑inch of the root.
Key visual cues:
- Color: dandruff appears white or gray; nits range from yellow‑white to brown, often matching the hair color.
- Surface: flakes are powdery and crumble under a fingertip; nits are smooth, translucent, and do not break apart.
- Position: dandruff can be scattered across the scalp and shoulders; nits are aligned in a line along the hair shaft, often on the underside where they are less visible.
Physical tests:
- Light pressure: gently pinch a suspected particle between two fingers. Flakes will slide off; nits remain attached.
- Wetting: soak the hair in water for a few minutes. Dandruff dissolves or flutters away, while nits stay adhered.
Microscopic examination confirms identification. Under 40–100× magnification, nits display a defined shell with a visible operculum (cap), whereas dandruff shows irregular, flaky edges without a defined structure.
Treatment implications:
- Flakes respond to antifungal shampoos containing zinc pyrithione or selenium sulfide.
- Nits require mechanical removal with a fine‑tooth comb and, if live lice are present, an insecticide shampoo.
To avoid confusion, inspect hair in bright light, separate sections, and compare particles against the criteria above. Consistent identification prevents unnecessary medication and ensures appropriate care.