If you’ve noticed that one or more of your toenails or fingernails is discolored, thickened, or brittle, you might have onychomycosis, a common fungal infection that many people simply call nail fungus. Onychomycosis can significantly impact your quality of life, and studies show that it affects almost 14% of adults in North America.
Treating nail fungus can be tricky because the infection often recurs, and it can be hard to stick to the treatment plan. Also, some fungi are becoming resistant to certain medications, making them harder to eradicate.
Two of the most commonly prescribed oral antifungal medications are terbinafine and itraconazole. Terbinafine is often the first choice for oral treatment, while itraconazole is another option that comes with its own set of benefits and risks.
This article provides a comprehensive overview of terbinafine and itraconazole as treatments for onychomycosis, or nail fungus, including how well they work, what side effects they can cause, what to consider before taking them, and what kind of results you can expect.
Understanding onychomycosis
Onychomycosis is the medical term for a nail fungal infection. It’s worth understanding how these infections start, who gets them, and how doctors diagnose them before diving into treatment options like terbinafine and itraconazole.
What causes onychomycosis?
Dermatophytes, a type of fungus, are the main culprits in about 70% of nail fungus cases in the U.S. Trichophyton rubrum is the most common dermatophyte to blame. But sometimes, non-dermatophyte molds and yeasts, such as Candida, can also cause these infections.
These fungi invade the nail bed and the nail plate itself. Once they’re in there, they cause the nail to thicken, change color, and even separate from the nail bed. The fungi can also form a biofilm, which is like a protective shield that makes them harder to treat.
Who gets nail fungus?
Nail fungus is more common as people age. More than 20% of adults over 60 and over half of people over 70 are affected by it. People with diabetes and those with weakened immune systems are also more likely to get nail fungus.
How is nail fungus diagnosed?
It’s important to make sure it’s really a fungal infection before starting treatment. Doctors use a few different methods to diagnose onychomycosis.
A KOH preparation with microscopy is often the first test. This involves taking a sample from under the nail and looking at it under a microscope to see if there are any fungi present.
A fungal culture can identify the specific type of fungus causing the infection. In some cases, a biopsy with a PAS stain might be necessary to confirm the diagnosis.
It’s also important to rule out other nail disorders that can look like onychomycosis, such as psoriasis or lichen planus.
Terbinafine: How it Works, How Well it Works, and What to Watch Out For
How Terbinafine Works
Terbinafine fights nail fungus by targeting a specific enzyme called squalene epoxidase. This enzyme is essential for fungi to produce ergosterol, a vital building block of their cell membranes.
Terbinafine puts a stop to ergosterol production, leading to a shortage of this crucial component. Without enough ergosterol, the fungal cells can’t survive, and the infection clears up.
How Well Terbinafine Works
Clinical trials have shown that terbinafine is highly effective at getting rid of toenail fungus. Studies suggest that taking terbinafine continuously leads to better results than pulse dosing (taking it for a short period, stopping, and then starting again).
Cure rates for toenail fungus with terbinafine range from about 38% to 76%. When it comes to toenail infections, terbinafine often works better than itraconazole.
Safety and Side Effects
Like all medications, terbinafine can cause side effects. The most common ones include:
- Headache
- Upset stomach
- Skin rashes
Although rare, more serious side effects can occur, including liver problems. Your doctor may want to monitor your liver function with blood tests while you’re taking terbinafine.
Terbinafine can also interact with other medications, especially those processed by enzymes called CYP450. Be sure to tell your doctor about all the medications you’re taking before starting terbinafine.
Itraconazole: How it Works, How Well, and What to Watch Out For
Itraconazole is another oral antifungal medication prescribed for nail fungus. Let’s take a closer look at how it works, how well it works, and what you should watch out for if you’re prescribed this medication.
How It Works
Itraconazole works by interfering with a key enzyme that fungi need to create ergosterol, a vital component of their cell membranes. Without ergosterol, the fungal cell membranes become unstable, leading to cell death and clearing the infection.
How Well It Works
Itraconazole has been proven to work against onychomycosis. However, the rates of success vary considerably. Studies show that itraconazole clears toenail infections somewhere between 14% and 63% of the time. In general, terbinafine is considered more effective for toenail infections.
Safety and Side Effects
As with any medication, itraconazole can cause side effects. The most common include:
- Headache
- Gastrointestinal problems like nausea, vomiting, or abdominal pain
- Upper respiratory infections
More seriously, itraconazole can, in rare cases, cause liver toxicity and heart problems. Also, itraconazole interacts with a number of other drugs because of its effect on CYP450 enzymes. Because of this, it’s essential to make sure your doctor knows about all the other medications you’re taking.
It’s worth noting that both terbinafine and itraconazole require a prescription and monitoring by a healthcare professional due to the potential for side effects and drug interactions. The best course of action is to consult with a healthcare provider to determine the most suitable treatment option for your specific situation.
What to consider if you’re thinking about oral antifungals
Before you decide whether to take terbinafine or itraconazole, here are a few things to discuss with your doctor:
Other illnesses
If you have diabetes or HIV, you should know that people with these conditions are more likely to develop nail fungus. Experts estimate that more than 23 percent of HIV-positive people have nail fungus, versus less than 7 percent of people who don’t have immune problems.
Pregnancy and breastfeeding
If you are pregnant or breastfeeding, discuss the risks and benefits of all medications with your doctor. Terbinafine is generally not recommended during pregnancy or breastfeeding. Itraconazole is not safe during pregnancy.
Children
Oral antifungal medications are not commonly used in children because there’s not a lot of research about their safety and effectiveness in this age group. For mild cases of nail fungus in children, topical treatments may be preferred.
Drug interactions
It’s very important to review all the medications you’re taking with your doctor before starting treatment with terbinafine or itraconazole. These medications can interact with other drugs, potentially causing serious side effects.
Here are a few examples of drugs that can interact with terbinafine or itraconazole:
- Certain antidepressants and anti-anxiety medications
- Some heart medications
- Some antibiotics
- Certain medications for high blood pressure
- Some pain medications
- Blood thinners
Be sure to tell your doctor about all medications, supplements, and herbal remedies you’re taking to avoid potentially dangerous interactions.
Because it can take months to see results from these medications, it’s important to have all the information you need to make the best choice for your health.
What else can you do?
Sometimes, the best thing to do is to combine treatments. For example, you might take terbinafine and also use a topical treatment. Here are some other treatments you can try.
Topical therapies
If you’re looking for a topical treatment, you have some choices. Ciclopirox, efinaconazole, and tavaborole are all available with a prescription.
Keep in mind that topical treatments don’t work as well as oral treatments. If your infection is severe, or if you have other health conditions, your doctor may recommend that you take an oral medication, such as terbinafine or itraconazole, instead.
Surgical and laser therapies
In very severe cases, your doctor may recommend that you have the nail removed. This is called surgical nail avulsion. I know, it sounds terrible!
You may also want to consider laser therapy. Laser therapies can be an alternative when medical therapy isn’t successful.
Integrative medicine
Some people also try essential oils and other natural remedies. While there’s not much research in this area, some people find these remedies helpful.
Frequently Asked Questions
Can itraconazole and terbinafine be taken together?
No, itraconazole and terbinafine should generally not be taken together. They both target fungal infections, but combining them can increase the risk of side effects and drug interactions. Always consult your doctor before taking any new medication, especially when you’re already on other treatments.
What gets rid of nail fungus permanently?
While complete eradication can be challenging, oral antifungal medications like terbinafine and itraconazole offer the best chance for permanent resolution of nail fungus. However, even with treatment, recurrence is possible. Consistent hygiene practices and addressing underlying health conditions can help minimize the risk of reinfection.
Is terbinafine or itraconazole better for toenail fungus?
Terbinafine is often considered the first-line treatment for toenail fungus due to its higher cure rate and shorter treatment duration compared to itraconazole. However, the best choice depends on individual factors, including the type of fungus, your medical history, and potential drug interactions. Your doctor will determine the most suitable option for you.
How to tell if terbinafine is working on toenail fungus?
It can take several months to see noticeable improvement. As the infected nail grows out, you should observe new, healthy nail growth at the base of the nail. It’s essential to continue taking the medication as prescribed, even if you don’t see immediate results.
How long does it take for nail fungus to go away with terbinafine?
The duration of terbinafine treatment typically ranges from 6 weeks for fingernail infections to 12 weeks for toenail infections. However, it can take several more months for the infected nail to fully grow out and be replaced by healthy nail tissue. Patience and adherence to the prescribed treatment plan are crucial.
Key Takeaways
If you’re dealing with a nail fungus infection, terbinafine is often the first oral treatment your doctor will consider. Itraconazole is another option, but it’s important to consider its potential side effects and how it might interact with other medications you’re taking.
Before you start taking any medication for nail fungus, make sure you actually have a fungal infection. Not all nail problems are caused by fungus! It’s also important to work with your doctor to choose the treatment that’s best for you, considering your overall health and any other conditions you might have. Keep in mind that it takes time for nails to grow back normally, so be patient and don’t expect overnight results.
While terbinafine and itraconazole are the most common treatments, researchers are always looking for new and better ways to treat nail fungus. New treatment options are being studied, but more research is needed to confirm that these new treatments are safe and effective.