NO DRUG THERAPY IN PRIMARY CARE (ASSESS FIRST)
Confirm what it is before treating it. Fewer than half of thickened, discoloured nails are fungal - psoriasis, repeated trauma, lichen planus and chronic paronychia all look the same. Where it matters, and always before committing to a months-long antifungal course, send nail clippings for microscopy and culture. Look at all twenty nails, the nail folds, and the skin of the soles, palms, scalp and elbows. - Assess, then decide
Nail changes in children are far more often trauma, nail biting or eczema than fungus. Amorolfine lacquer is not for children; confirmed onychomycosis in a child should be referred.
No dose - assessment step, no medicine given
An oral antifungal course runs for months and needs liver monitoring; a lacquer runs for up to a year. Neither is worth starting on a guess, and a nail that was never fungal will not improve - which then gets read as treatment failure rather than as the wrong diagnosis.
- A single new dark streak running the length of one nail, particularly if the pigment spreads onto the nail fold, is subungual melanoma until proved otherwise. Refer urgently.
- Clubbing is not a nail disease. It points at the chest, the heart or the bowel - examine accordingly.
- Pitting, oil-drop discolouration and onycholysis across several nails is psoriasis. An antifungal will do nothing for it.
- A painful red swollen nail fold is paronychia. That is treated as an infection or drained, not with an antifungal.
- In a diabetic or anyone with poor circulation, a thickened nail is a foot-care problem first - refer to podiatry, and never let a patient cut it back aggressively themselves.
- Brittle, spooned or ridged nails: check ferritin and thyroid function rather than reaching for a topical.