Nail Fungus Treatment in Hong Kong: Terbinafine and Itraconazole

One toenail has been thick and yellow for so long you have given up cutting it straight. It began at the edge, as these usually do. Now it is opaque, a bit crumbly, and lifts when you press it. Hong Kong calls this 灰甲, and a lot of people start with a brush-on liquid.

What has been tested properly is a short list: terbinafine tablets, itraconazole capsules, amorolfine lacquer and ciclopirox lacquer. This article sets out what the trials and the official labels say about each, including how long you wait before the nail looks normal.

In short

• A thick nail is not automatically a fungal one. Psoriasis and old injuries look similar, so get it confirmed before committing to months of treatment.
• Terbinafine tablets have the strongest evidence of the oral options, and the Cochrane review found them probably more effective than the azoles.
• The medicine clears the infection within weeks, but the damaged nail has to grow out, which can take a year or more.
• Treating athlete's foot promptly and keeping feet dry makes a second infection less likely.

How do you know it is a fungus and not something else?

The nail has looked wrong since last summer, and the surface is uneven enough that a sock catches on it. A fungal infection usually affects toenails rather than fingernails, begins at the edge and makes the nail thicker, white or yellow, brittle and crumbly. Sometimes the nail lifts off the nail bed altogether. It is not serious, but it can take a long time to treat (NHS).

Not every thick, discoloured nail is fungal. Nail psoriasis and an old injury can look very similar, which is why a dermatologist will often take a clipping or a scraping and look at it under a microscope (AAD). The check matters because tablets are taken daily for weeks, and you want to be sure of the target first.

Three reasons to get a nail checked rather than treating it yourself: pain, spread to other nails, and diabetes or a weakened immune system (NHS). The amorolfine label adds poor circulation in the limbs to diabetes and immunosuppression (SmPC).

Why do tablets work better than lacquer?

There is a half-used bottle of lacquer in the bathroom cabinet and the nail has not changed. A lacquer dries into a film on the surface of the nail plate, while the infection sits in and under the plate. The Cochrane review notes that topical treatments have traditionally had low success rates because of the nail's physical properties (Cochrane 2017).

Pharmacy brush-on medicines are used daily or weekly depending on the type, for six to twelve months, and several months pass before any improvement shows (NHS).

The evidence for tablets is stronger. The Cochrane review pooled 48 studies with 10,200 participants and found high-quality evidence that terbinafine beats placebo for clinical cure (risk ratio 6.00) and mycological cure (4.53), and that azoles beat placebo too. Terbinafine was probably more effective than the azoles for both clinical cure (0.82) and mycological cure (0.77), with probably no difference in adverse events.

Put the cure rates side by side, but not as a league table: the trials differ in design, in which nails were included and in how cure was defined. Ciclopirox lacquer, applied for 48 weeks with monthly removal of unattached nail by the investigator, gave complete cure in 5.5% (6 of 110) of patients in one US trial and 8.5% (10 of 118) in another, against 0.9% and 0% on the vehicle (DailyMed, ciclopirox). In the terbinafine toenail study, 70% had mycological cure and 38% had mycological plus clinical cure, meaning the nail was fully clear as well (SmPC).

Amorolfine is licensed for mild cases limited to two nails: applied once a week after filing the nail and cleaning it with an alcohol pad, generally for six months on fingernails and nine to twelve months on toenails, with a review about every three months (SmPC). For one mildly affected nail that is a fair thing to try. For a crumbly big toenail that has been bad for a year, it is a slow route.

How is terbinafine taken, and for how long?

It is one 250 mg tablet a day, and the leaflet says twelve weeks. That feels long. Six weeks is generally enough for fingernails and twelve usually enough for toenails, but a few people whose nails grow poorly need six months or longer (SmPC). Feeling sick on it? Taking it after a meal or snack can help (NHS).

The common side effects are rash, headache, diarrhoea and feeling or being sick, each affecting more than one in a hundred people (NHS, same page). The SmPC also lists taste disturbance. It usually recovers within several weeks of stopping, though isolated cases of prolonged loss of taste have been reported.

The liver is the part that deserves attention. Terbinafine is not recommended in chronic or active liver disease. A liver test is advised before starting and monitoring at four to six weeks. Stop the tablets and get your liver checked if you develop nausea, loss of appetite, vomiting, pain under the right ribs, jaundice, dark urine or pale stools. Very rare cases of serious liver failure have been reported, most in people with serious underlying illness (SmPC).

Two details follow from how the drug behaves. It concentrates in skin, nails and hair and is still there 15 to 20 days after the last tablet. It also blocks CYP2D6, an enzyme that clears some tricyclic antidepressants, SSRIs, beta-blockers and antiarrhythmics, so those combinations need checking (SmPC, same page).

What about itraconazole, and where does griseofulvin fit?

Itraconazole comes with different instructions: a full meal, pulses for some nails, and a long list of medicines you cannot mix it with. Capsules are taken straight after a full meal, because absorption is best with food and falls when stomach acid is low (DailyMed, Sporanox). The US label gives 200 mg (two 100 mg capsules) once daily for twelve weeks for toenails. For fingernails alone it is two one-week pulses of 200 mg twice daily, with three weeks off between them. Take an antacid two hours before or after the capsule (MedlinePlus).

The toenail trials behind that label found mycological cure in 54%, overall success in 35% and mycological plus clinical cure in 14%, with a mean time to overall success of about ten months. Of those who succeeded, 21% relapsed.

Itraconazole has more ways to go wrong than terbinafine. It should not be used for nail fungus by anyone with heart failure or a history of it. Shortness of breath, coughing up white or pink phlegm or unusual tiredness mean stop and call a doctor (MedlinePlus). Serious liver injury is rare but has occurred, some of it within the first week. The interaction list is long and includes simvastatin and lovastatin, both contraindicated. If you could become pregnant, treatment for nail fungus starts on the second or third day of a period, with effective contraception during treatment and for two months after.

Griseofulvin is the older oral option. The Cochrane review found azoles and griseofulvin similar in efficacy, with griseofulvin probably causing more adverse events, and low-quality evidence that terbinafine may work better with fewer of them.

Why does the nail still look bad months after the course?

Twelve weeks of tablets done, and the nail looks as yellow as in week one. That is expected. The medicine stops the fungus growing, but the damaged nail stays until new nail pushes it out. Per the terbinafine label, complete resolution may not show until several months after stopping, which matches the time a healthy nail takes to grow (SmPC).

The AAD is more specific about the big toenail: the infection can clear while the discolouration stays, and it may take a year or longer to see a clear nail (AAD). You may also see "12 to 18 months" quoted. In the AAD's wording that is how long a toenail takes to regrow after it has been removed, so treat it as a regrowth figure, not a promise for a course of tablets (AAD).

Look for new, healthy nail at the base. That is the sign the infection has gone, and it appears long before the whole nail has changed (NHS).

How do you stop it coming back in Hong Kong's warm, damp weather?

The big toenail is finally clear and the worry is the other foot. The NHS names feet that stay warm and damp, long hours in trainers and hot, sweaty feet as the conditions that make infection more likely (NHS). In a warm, humid city those are easy to come by, so the habits below carry weight.

Athlete's foot first. The same fungus can move from skin to nail, and many people do not realise they have it (AAD), so treat athlete's foot as soon as it appears. Then: keep nails short and feet clean and dry, put on clean socks daily, wear flip-flops in gym and pool showers, pick shoes that fit without narrow toes or high heels, and bin old shoes. Towels, shoes, nail clippers and scissors are not for sharing (NHS).

Some risk stays. Nail fungus can return a year or more after clearing, and once you have had it you are more likely to get it again (AAD).

Which nail fungus medicines does PockDose list?

PockDose lists no nail lacquers, so the amorolfine and ciclopirox rows in the comparison table are there for context. Ordering from PockDose needs no prescription.

Choose by the nail affected: terbinafine runs six weeks for fingernails and twelve for toenails. If you take anything for your heart, cholesterol or mood, read the product page before you order, and tell whoever looks after your health which tablets you are taking. The nail fungus page shows what is listed for this condition, and the antifungals category has the wider range; the terbinafine and itraconazole pages cover each ingredient.