What it is
The visit starts by establishing which of these it is, using dermoscopy of the nail and a clipping sent for microscopy and culture, because a great deal of what is called "fungus" turns out to be something else and is then treated for months with the wrong tablet. A pigmented band running lengthways along a nail is assessed separately and carefully, because it is occasionally the first sign of something that needs a biopsy.
What this page covers
- Nail sampling before treatment: clipping, KOH microscopy, culture and onychoscopy
- Onychomycosis, confirmed in the laboratory before any oral course, with liver function and drug-interaction review
- Nail psoriasis: pitting, oil-drop change, onycholysis and subungual thickening
- Nail lichen planus, which needs early treatment because matrix scarring does not reverse
- Acute and chronic paronychia, including the cuticle-pushing, nail-biting and unprotected-detergent causes of the chronic form
- Ingrown toenail: local care, partial nail avulsion, and phenol matricectomy for the recurrent case
- Brittle nails, assessed alongside iron and thyroid rather than treated with high-dose biotin
- Habit-tic deformity, which is diagnosed clinically and routinely mistreated as fungus
- Gel, acrylic and polygel damage, and true (meth)acrylate contact allergy — which also presents as facial and eyelid dermatitis by transfer
- Longitudinal melanonychia: dermoscopy, photographic documentation and the biopsy threshold
- Acral and nail melanoma recognition in skin of color, including Hutchinson sign
- Nail unit biopsy and nail surgery, with the possible lasting nail-plate change stated in the consent conversation
- Foot assessment and earlier referral in diabetes and poor circulation, where any nail wound complicates
Who it suits
- Someone given a course of tablets for nail fungus without a clipping ever being sent for microscopy and culture, whose nail then did not change
- Someone whose toenail keeps ingrowing, or whose nail fold keeps getting inflamed, and who wants the reason it recurs dealt with rather than the same trim repeated
- Someone whose nails have changed together — lengthwise ridging, thinning, splitting — and who wants an early opinion, because scarring of the nail matrix does not reverse
- Someone whose face and eyelids have been treated for months as "sensitive skin" while the skin around the nails is inflamed and the manicures continue
- Not you if you want the tablets without the sample that comes before them, or a nail returned to exactly the shape it had. Treating a nail is usually elective, it is slow, and it moves at the speed the nail grows; a nail that neither hurts nor bothers you can be left alone and watched, and that is a legitimate decision we will say out loud and write in the file
When we advise delaying or not treating
- Tablets for nail fungus before the sample comes back. We do not start a long oral course on a guess. And any antifungal cream or lacquer is stopped before the clipping is taken, for the period you are given, or the result comes back negative when it is not
- Pregnancy and breastfeeding, and anyone who could become pregnant. We defer all the oral antifungals. A nail is not urgent and can wait; it is managed in the meantime with trimming, thinning and topical care
- Itraconazole for anyone taking a cholesterol tablet in the statin family or certain heart-rhythm medicines, and for anyone with heart failure. It raises the level of a long list of other medicines in the blood, which is why the whole list is reviewed before it — including what is bought without a prescription, herbal products and supplements, and anything brought from outside the Kingdom
- Terbinafine in known liver disease, and before liver function has been checked. Whoever prescribes it is also told if you have lupus or a history of it
- Phenol matricectomy in poorly controlled diabetes, in poor circulation to the legs, and in neuropathy. The wound here is small but slow, and a foot that cannot feel and is not well supplied belongs with a diabetic foot service rather than in a passing clinic appointment
- Gel, acrylic or polish over a nail that has changed color or shape and has not been diagnosed. We decline. Covering it postpones the question rather than answering it, and it hides from the examination the very thing being measured
- A request for an appointment that will have the nail finished before an occasion or a trip. We do not tie a result to a date. Nails grow slowly and a toenail more slowly still, and what is judged at review is the newly grown part near the base, not what is left of the old nail
- High-dose biotin for brittle nails. It is not handed out without a reason: it interferes with thyroid and cardiac blood tests so that results are read wrongly. The useful step is assessing iron and thyroid, and reviewing acetone, repeated polish removal and extensions
- Treating a thickened nail as fungus when shoes, sport and repeated knocks are the cause. No antifungal corrects that, however long the course runs
Possible effects
Stated in full, because the decision is not sound without them:
- Terbinafine: disturbance of taste and smell — food tastes of nothing, or of metal, and appetite can drop with it. It usually returns after the drug is stopped, but it can take a long time, and in a small number of people it does not come back quite as it was. Liver injury is rare but real, and its signs are in the box at the top of this page. A severe rash can occur, and it can bring out or worsen cutaneous lupus
- Itraconazole: its first hazard is not the drug alone but the drug in company — it raises the level of many other medicines in the blood. It also causes nausea, stomach discomfort and headache, and it can produce the symptoms of heart failure: swollen ankles, breathlessness, and breathlessness on lying flat. Those are reported as soon as they appear rather than saved for the review
- Both are preceded by liver function tests and a review of your medicine list, with monitoring afterward as the prescriber sets it
- Topical antifungal lacquer: gentler on the body because nothing is swallowed, but it asks for long and consistent application, and it can irritate the skin at the nail fold
- Partial nail avulsion: pain as the block wears off, some bleeding, a risk of infection, and the ingrowing coming back if the edge is removed and the matrix that produced it is left as it was
- Phenol matricectomy: said before consent, not after the procedure. The treated strip of nail is not expected to grow back, so the nail stays narrower than it was — that does not reverse, and written consent is taken for it. The neighboring skin can take a chemical burn, healing is slower than after surgery, and it is preceded by a long discharge phase: dressings changed for weeks rather than days, and no closed shoes and no sport for a period you will be given
- Nail unit biopsy: it can leave a lasting mark in the nail plate — a ridge, a split, a narrower or a thinner nail. That belongs in the consent conversation before the biopsy, not as a surprise afterward. Sampling for fungus is something else entirely: a clipping, not surgery
- Nail lichen planus left alone: scarring of the nail matrix does not reverse, and the nail can be lost and not come back. That is a reason to bring the appointment forward, not a reason to be frightened
- Acrylate allergy: once it has developed it does not go away, and it cross-reacts with other acrylate-containing materials — dental fillings, bone cement, some adhesives and medical device glues. It is confirmed by patch testing to an acrylate series, which is not in the standard panel every time and has to be asked for by name, and your dentist and any surgeon are told about it afterward
A note on darker skin
Skin tone does not change the anatomy of a nail, but it changes three practical things. The first is that several even pigmented bands across more than one nail are common and physiological in brown and darker skin, and are not alarming in themselves — but they are examined with dermoscopy and photographed at the first visit rather than assumed, because "that is normal in your skin" is exactly the sentence later used to wave away the one band that is behaving differently from the rest. The second is that the place to be careful is the skin around the nail rather than the nail itself: inflammation of the nail fold, removal of a strip of nail, and the phenol burn on the neighboring skin all leave post-inflammatory darkening that is more pronounced on deeper skin and takes months to even out. That is the footprint of healing rather than the problem returning, and it is not treated with a lightening cream or a mixed cream over a wound that has not closed; if a mixed cream is already in use, bring it with you in its container. A tendency to keloid is asked about before any procedure on a finger or toe. The third is that skin tone is not in itself a reason to avoid the 1064 nm Nd:YAG laser on a nail — that wavelength is the one usually chosen in darker skin — and the limit here is the strength of the evidence rather than the skin type, with the laboratory sample coming first in any case.
Afterwards
- Cut toenails straight across rather than curved down at the corners, and wear shoes with room across the front of the foot. Rounded cutting and a tight shoe are the recurring cause of ingrowing, and both are corrected before any procedure
- Gloves for detergents and wet work, and stop pushing the cuticle back and biting the nails. Chronic inflammation of the nail fold does not settle while that continues, whatever the cream is
- Come with the nail as it is: no polish, no gel and no extension on the nail in question, and on the day the sample is taken in particular. Stop any topical antifungal before it, for the period you are given
- Photograph the nail on your phone against a plain background in the same lighting, and repeat the photograph at intervals. A nail changes slowly and memory is a poor witness; the photograph is what gets compared
- While you are on tablets for nail fungus, report straight away: yellowing of the eyes or skin, dark urine, nausea that will not settle, pain under the right ribs, or unusual tiredness — see the box at the top of this page. Report a change in taste or smell too, and swollen ankles or breathlessness, and any new rash. Tell every doctor and pharmacist who prescribes for you that you are taking them, and tell us about any new medicine, herbal product or supplement you start
- After any procedure on a nail: leave the dressing as you were shown, and expect discharge to continue — that is expected and does not mean something has gone wrong. Keep to the period you were given with no closed shoes and no sport
- Come to the review even if the nail looks the same. What is assessed is the newly grown part near the base rather than what is left of the old nail, and that is the difference between treatment that is working slowly and treatment that is not working
Honestly
Nails grow slowly, so improvement follows that pace and a nail may not go back to the shape it had before. Not every thickened yellow nail is fungal. A single dark band running down one nail is the one to have looked at soon — more so when it is new after childhood, when it is widening or darkening, when its lines are uneven, when it spreads onto the skin around the nail, or when the nail splits along it. A bruise from a knock travels up and grows out over the months; a band that stays where it is, or keeps changing, is a biopsy question rather than a cosmetic one — it should not be covered with polish or an extension, and it should not be left to see whether it grows out. Nail melanoma is diagnosed late in exactly this skin, and the months before the visit are usually the reason.
Common questions
My toenail is thick and yellow — can you just give me the tablets?
We start with a clipping sent for microscopy and culture, together with dermoscopy of the nail. The reason is that a great deal of what gets called fungus is not fungus: it can be psoriasis in the nail, lichen planus, or repeated trauma from a shoe, and no antifungal corrects those however long the course runs. If you are using an antifungal cream or lacquer, stop it before the sample for the period you are given, or the result comes back negative when it is not. The sample takes its time, but it saves months of a medicine you did not need.
And if I decide not to take the tablets at all?
That is your decision, it is legitimate, and it is respected. Treating a nail is usually elective: a matter of appearance and comfort rather than something imposed on you. A nail that neither hurts nor bothers you can be left alone and watched, or managed with a topical lacquer and care over trimming and thinning. The exception is said plainly: with diabetes or poor circulation an affected nail is not a matter of appearance — cracked skin and a crumbling nail are a way in for infection, and any wound on that foot complicates, so there we press the point and arrange a foot assessment. The same is true if the nail is painful, or if fungus has spread across the skin of the foot — see skin infections.
Do the tablets harm the liver? And I take other medicines.
A fair question, and the reason they are not handed out without a review. Terbinafine can injure the liver; that is rare but real, so liver function is checked before it and the signs listed in the box at the top of this page are reported as soon as they appear. What troubles people most in practice, though, is the change in taste and smell. Itraconazole's first problem is interaction: it raises the level of many other medicines in the blood, it is not combined with cholesterol tablets in the statin family or with certain heart-rhythm medicines, and it is not given in heart failure. Bring a list of everything you take — prescribed and not, herbal products and supplements, and anything brought from outside the Kingdom — and which of the two suits you, or neither, is decided after that.
I am pregnant or breastfeeding.
We defer the oral antifungals. A nail is not urgent and can wait, and this is one of the few places where waiting costs almost nothing. In the meantime we deal with what actually bothers you: trimming and thinning, care of the skin around the nail, a topical treatment where it suits, and treating any fungus on the skin of the foot. And if you are planning a pregnancy soon, say so before we start rather than after.
Does laser clear nail fungus?
We will say it as it is: the evidence for laser here is weaker than the evidence for drug treatment, and the session is uncomfortable. The same condition still applies — the sample first, because laser over nail psoriasis or repeated trauma will do nothing. Its reasonable place is someone who cannot take the tablets or chooses not to, and even then what can and cannot be expected is said before it starts rather than after it finishes.
My ingrown toenail keeps coming back — why?
Because what is usually removed is the edge of the nail alone, and the matrix that produced that edge is left as it was, so it grows again. The procedure that stops the recurrence treats that strip of matrix with phenol, and it has a price that has to be known before consent rather than after: that strip is not expected to grow back, so the nail stays narrower in shape; healing is slow and comes with discharge; dressings are changed for weeks rather than days; and closed shoes and sport stop for a period. Even so we start with the simplest thing: correcting how the nail is cut and what shoe is worn, because those are the recurring cause, and many cases need nothing beyond it.