Understanding the Chemicals in Over-the-Counter Nail Fungus Treatments

Understanding the Chemicals in Over-the-Counter Nail Fungus Treatments

Nail fungus, also known as onychomycosis, is a common condition affecting millions of people worldwide. It is a fungal infection that affects the nails of fingers and toes, causing discoloration, thickening, and deformity. The condition can be unsightly and painful, and it can also lead to serious complications if left untreated.

Fortunately, there are several over-the-counter (OTC) nail fungus treatments available. However, these treatments contain various chemicals that may not be familiar to everyone. Understanding the chemicals in OTC nail fungus treatments is essential for selecting the right product for your needs.

In this article, we will explore the active ingredients commonly found in OTC nail fungus treatments and their mechanisms of action. We will also discuss the potential side effects associated with these chemicals and how to use these products safely and effectively. By gaining a better understanding of these treatments’ chemical composition, you can make informed decisions about managing your nail fungus symptoms.


Azoles are a class of antifungal drugs commonly used in the treatment of nail fungus. These medications work by inhibiting the production of ergosterol, a vital component of the fungal cell membrane.

Some examples of azole antifungals include clotrimazole, miconazole, and ketoconazole. These drugs are available in various forms such as creams, gels, and sprays for topical application or as oral tablets or capsules.

Azoles have been shown to be effective against a wide range of fungal infections including candidiasis, ringworm, and jock itch. However, prolonged use can lead to the development of drug-resistant strains of fungi.

Moreover, these drugs may interact with other medications leading to adverse effects such as liver damage and gastrointestinal upset. As such, it is important to use azole antifungals only under medical supervision and after a proper diagnosis has been made.


Imagine a team of construction workers building a house. Each worker has a specific job to do, and they all work together to build the entire structure. Terbinafine is like the foreman of this team; it directs the other chemicals in over-the-counter nail fungus treatments and makes sure they are working together efficiently.

This antifungal medication is known for its ability to kill fungi by interfering with their cell membranes, leading to their death. When applied topically or taken orally, terbinafine can effectively treat nail fungus infections.

Here are four key things to know about terbinafine:

  1. Terbinafine is considered a broad-spectrum antifungal agent that can target multiple types of fungi.
  2. It may take several weeks or months of consistent use for terbinafine to completely eradicate nail fungus.
  3. In rare cases, terbinafine may cause side effects such as liver damage or skin reactions.
  4. Terbinafine should be used as directed by a healthcare professional and should not be shared with others.

Overall, terbinafine plays an important role in the effectiveness of over-the-counter nail fungus treatments by acting as the leader of the chemical team responsible for eliminating fungal infections.


As discussed in the previous section, Terbinafine is a popular over-the-counter nail fungus treatment that works by inhibiting the growth of fungal cells.

Another effective antifungal agent commonly found in over-the-counter nail fungus treatments is Tolnaftate. This compound works by preventing the formation of fungal cell membranes, ultimately leading to their destruction. Tolnaftate has been shown to be particularly effective against dermatophytes, a type of fungus responsible for many cases of nail infections.

Like Terbinafine, Tolnaftate is available in various forms such as creams, powders, and sprays designed for topical application.

While both compounds have proven efficacy in treating nail fungus infections, it is important to note that they may not work for everyone and consulting a healthcare professional before starting any medication is recommended.

Undecylenic Acid

Undecylenic acid is a naturally occurring fatty acid derived from castor oil and has antifungal properties.

It is a common active ingredient found in many over-the-counter nail fungus treatments.

The acid works by disrupting the fungal cell membrane, leading to its death.

It has been found to be effective against various types of fungi that can cause nail infections.

However, the exact concentration required for optimal efficacy is still unclear.

Undecylenic acid has also been used in other medical applications, such as treating skin conditions like athlete’s foot and ringworm.

In general, it is considered safe for use and has few side effects.

However, it may not be suitable for individuals with sensitive skin or allergies to castor oil.

Other Ingredients

Other Ingredients:

Aside from the active antifungal ingredients, over-the-counter nail fungus treatments may contain other ingredients that serve various purposes. These can include moisturizers, vitamins, and essential oils that aim to promote healthy and nourished nails. Other ingredients may also act as preservatives or emulsifiers to help keep the product stable and free from contamination. However, it is important to note that some of these additional ingredients may cause adverse reactions or allergies for some individuals. It is recommended to carefully read the label and consult with a healthcare professional before using any over-the-counter nail fungus treatment.

IngredientPurposePossible Side Effects
UreaMoisturizes and softens nailsMild skin irritation
Tea tree oilNatural antifungal propertiesSkin irritation, allergic reactions
Jojoba oilMoisturizes and strengthens nailsNone reported
Vitamin E oilPromotes nail growth and nourishmentNone reported
Propylene glycolPreservative and emulsifierSkin irritation, allergic reactions

It is important to note that while these ingredients are generally deemed safe, they may interact with other medications or cause unexpected side effects in certain individuals. As such, it is always recommended to exercise caution when using over-the-counter nail fungus treatments containing additional ingredients. Consulting with a healthcare professional or dermatologist can provide further guidance on which products would be best suited for individual needs.


The chemicals in over-the-counter nail fungus treatments are essential in inhibiting the growth of fungi responsible for nail infections. The most commonly used chemicals include azoles, terbinafine, tolnaftate, and undecylenic acid. These chemicals have different mechanisms of action but ultimately work towards achieving the same goal.

Azoles are antifungal agents that inhibit the production of ergosterol, a vital component of fungal cell membranes. Terbinafine acts by inhibiting an enzyme responsible for the synthesis of ergosterol, leading to the death of fungal cells. Tolnaftate works by disrupting the membrane integrity of fungal cells, while undecylenic acid has both antifungal and antibacterial properties.

Besides these active ingredients, over-the-counter nail fungus treatments contain other additives like water, alcohol, glycerin, and urea. These compounds help to improve drug delivery and enhance efficacy.

In conclusion, understanding the chemicals in over-the-counter nail fungus treatments is critical in choosing an appropriate treatment regimen that effectively targets specific fungal infections. While these treatments may differ in their chemical composition and mechanism of action, they ultimately work towards achieving the same goal- eliminating stubborn nail infections caused by fungi.