Fungal infections, sometimes called dermatomycoses, are very common. They can affect many different parts of your body, especially your skin and nails. One of the most common fungal infections is tinea pedis, better known as athlete’s foot.
Two medications commonly used to treat fungal infections of the skin are tolnaftate and ketoconazole.
Tolnaftate is an antifungal medication that you can buy without a prescription. Ketoconazole comes in topical and oral forms, but you often need a prescription to get the topical version.
So, how do these two medications stack up against each other? We will compare tolnaftate and ketoconazole, looking at:
- how they work
- how well they work
- what they are used for
- their side effects
This information is designed to provide healthcare professionals and patients with the details they need to make informed decisions about fungal infection treatment options. This article can guide you toward the treatment choice that best fits your specific needs and circumstances.
How do tolnaftate and ketoconazole work?
Both tolnaftate and ketoconazole are antifungals, but they work in different ways and target different types of fungi.
Tolnaftate
Tolnaftate works by changing the shape of fungal hyphae and slowing down the growth of mycelium (the vegetative part of a fungus), but scientists don’t completely understand how it does this. Tolnaftate also blocks squalene epoxidase, which is needed for fungi to build their cell walls.
Tolnaftate is effective against Trichophyton, Microsporum, and Epidermophyton fungi. These fungi cause tinea infections, such as athlete’s foot, ringworm, and jock itch. Tolnaftate is usually ineffective against Candida (yeast) infections.
Ketoconazole
Ketoconazole is an azole antifungal. It stops fungi from making ergosterol, which is important for their cell membranes. By interfering with ergosterol production, ketoconazole weakens the cell membrane, which leads to the death of the fungal cell.
Ketoconazole has a wider range of activity than tolnaftate. It works against dermatophytes (like Trichophyton) and yeasts (Candida, Malassezia). This makes it useful for treating different kinds of fungal infections.
How well do they work for athlete’s foot?
Athlete’s foot is a fungal infection that can cause itching, burning, scaling, and cracking on the feet. Both tolnaftate and ketoconazole can treat it, but their effectiveness varies.
How well does tolnaftate work?
Tolnaftate can effectively treat athlete’s foot, but it generally has lower cure rates than some other antifungals. Some studies show cure rates around 64%.
The typical treatment lasts two to four weeks. Tolnaftate is easy to find over the counter, and most people tolerate it well, with a low risk of side effects.
How well does ketoconazole work?
Ketoconazole, especially the cream or other topical versions, like itraconazole cream, is another effective treatment for athlete’s foot. Azoles as a class of antifungals have shown cure rates around 47%.
How long you need to use ketoconazole depends on how severe the infection is and the specific product you use.
Ketoconazole has a broader range of activity, which is helpful if you don’t know the exact type of fungus causing the infection or if you suspect you have more than one type of fungal infection.
What else are they used for?
Both tolnaftate and ketoconazole can treat fungal infections, but they aren’t exactly interchangeable. Here’s a quick look at what each medication is typically used for.
Tolnaftate
Tolnaftate can be used to treat:
- Tinea pedis (athlete’s foot)
- Tinea cruris (jock itch)
- Tinea corporis (ringworm)
However, tolnaftate is not usually used for nail infections (onychomycosis).
Ketoconazole
Ketoconazole has a wider range of uses than tolnaftate. It can be used to treat:
- Seborrheic dermatitis. Ketoconazole shampoo is a common treatment for seborrheic dermatitis, a fungal skin condition that causes dandruff and scaling.
- Tinea versicolor. Ketoconazole is effective against tinea versicolor, which causes discolored patches on the skin.
In the past, doctors sometimes prescribed oral ketoconazole for systemic fungal infections. But because of its side effects and how it interacts with other drugs, it’s not prescribed very often anymore.
How to use tolnaftate and ketoconazole
Both tolnaftate and ketoconazole are medications, and you should use them as directed by a healthcare professional.
Tolnaftate
Tolnaftate is a topical medication, which means that you put it directly on your skin.
To use tolnaftate, apply a thin layer to the affected skin twice a day. Continue using the medication for two to four weeks, even if your symptoms improve. If you stop using it too soon, the fungal infection may return.
Tolnaftate comes as a cream, powder, spray, and solution.
Ketoconazole
Ketoconazole also comes in a form for topical application. You’ll want to apply a thin layer to the affected area once or twice a day, or as directed by your healthcare provider.
How long you’ll need to use ketoconazole depends on the condition you’re treating. Your doctor can help you understand how long you’ll need to use the medication.
Ketoconazole can also be taken orally. However, oral ketoconazole isn’t prescribed as often because it has more potential side effects and can interact with other medications. If your doctor prescribes oral ketoconazole, they will decide the dosage based on your specific infection.
Side effects and precautions
Like all medications, tolnaftate and ketoconazole come with the possibility of side effects. Here’s what to keep in mind:
Tolnaftate
In general, tolnaftate is well-tolerated by most people. The most common side effects are mild and don’t last long:
- Burning
- Stinging
- Itching
Be careful to avoid getting tolnaftate in your eyes, nose, or mouth. If you notice that your skin is becoming more irritated, stop using the product.
Ketoconazole
Ketoconazole can cause more side effects than tolnaftate, and the type of side effect depends on whether it’s a cream or a pill.
Topical side effects of ketoconazole may include:
- Local irritation
- Itching
- Burning
- Redness
- Allergic contact dermatitis
Oral ketoconazole can cause more serious side effects, such as:
- Liver toxicity
- Nausea
- Vomiting
- Hormonal imbalances
Because of these risks, doctors prescribe oral ketoconazole cautiously and only when other treatments haven’t worked for severe infections. If you’re using ketoconazole cream, avoid getting it in your eyes.
If you’re taking ketoconazole orally, your doctor will want to keep an eye on your liver function. Ketoconazole interacts with many other drugs, and people with liver disease shouldn’t take it.
Drug Interactions
Before using a new medication, it’s always important to consider drug interactions. Drug interactions happen when one drug affects the way another drug works in your body.
Tolnaftate
Because tolnaftate is a topical treatment, it’s absorbed into your system in minimal amounts. That means that tolnaftate has very few drug interactions.
Ketoconazole
Oral ketoconazole, on the other hand, has many drug interactions. That’s because of the way it’s processed in your body. It can interact with medications such as:
- warfarin
- phenytoin
- certain statins
Topical ketoconazole has fewer interactions, but you should still be cautious when using it with other topical medications. Talk to your doctor about any medications you’re taking before you use ketoconazole.
Frequently Asked Questions
What is the closest OTC to ketoconazole?
While there isn’t a direct, identical over-the-counter (OTC) replacement for ketoconazole, which is an antifungal medication often prescribed for fungal infections, some OTC antifungal options may offer relief for similar conditions. Look for products containing clotrimazole or miconazole, which are commonly found in creams and lotions for athlete’s foot and ringworm. Keep in mind that these alternatives might not be as effective for all types of fungal infections that ketoconazole treats.
Does tolnaftate work on seborrheic dermatitis?
Tolnaftate is primarily an antifungal medication used for conditions like athlete’s foot, jock itch, and ringworm. It’s generally not effective against seborrheic dermatitis, which is often linked to a yeast called Malassezia but also involves inflammation. For seborrheic dermatitis, other medications like ketoconazole, selenium sulfide, or zinc pyrithione are typically more suitable.
What is the permanent cure for seborrheic dermatitis?
Unfortunately, there is no known permanent cure for seborrheic dermatitis. It’s a chronic condition that can be managed with various treatments to control symptoms like scaling, itching, and redness. These treatments often need to be used long-term to keep the condition under control, as symptoms can return when treatment is stopped.
What are the risks of tolnaftate?
Tolnaftate is generally considered safe for most people when used as directed. Common side effects are usually mild and localized to the application site, such as mild burning, stinging, or itching. Allergic reactions are rare but possible. It’s important to follow the instructions on the product label and consult a healthcare professional if you experience any concerning side effects.
Why is ketoconazole no longer used?
Ketoconazole is still used, but its oral form has become less common due to the risk of serious side effects, particularly liver problems and adrenal gland issues. Topical ketoconazole (creams, shampoos) is still frequently used for fungal infections and seborrheic dermatitis, as the risk of systemic side effects is much lower with topical application.
In Summary
Tolnaftate is an over-the-counter antifungal cream that works well on dermatophytes. Ketoconazole is available in both topical and oral forms and treats a broader spectrum of fungi.
Tolnaftate usually doesn’t cause many side effects, but ketoconazole, especially when taken orally, can cause more serious side effects and interact with other drugs.
If you have a mild case of athlete’s foot, tolnaftate is a good first choice because you can buy it without a prescription and it’s generally safe to use.
If your infection is severe, doesn’t respond to tolnaftate, or you think it might be caused by yeast, ketoconazole might be a better option. But, you’ll need to take precautions and be monitored by your doctor.
The American Academy of Dermatology recommends trying topical treatments first.
No matter which treatment you think might work, including options like a fungi nail pen, it’s important to see a doctor for a diagnosis and treatment recommendation, especially if your symptoms don’t get better or get worse. It’s essential to confirm the fungal diagnosis through testing to make sure you’re treating the right condition.