Tolnaftate vs Clotrimazole

Tolnaftate and Clotrimazole are two commonly used antifungal medicines. This post compares benefits, medical uses, side effects and mechanism of action of both medicines.

Have you noticed redness and itching under your foot after a visit to your gym?

Beware as these might be early symptoms of a fungal infection. Fungal infections are very common among people who frequent locker rooms, gyms and communal swimming pools. The moist environment is ideal for fungal growth.

Fungi are small organisms that feed by breaking down living or dead tissue. The fungi that most commonly cause infections in humans are particularly attracted to a tough, waterproof type of tissue called keratin, which is present in skin, hair and nails. These fungi are known as dermatophytes.

Antifungal medicines are used to treat fungal infections, which are most commonly found on epidermal appendages such as skin, hair and nails.

You may be given an antifungal medicine to treat common fungal infections, such as:

• Ringworm – a ring-like red rash on the skin of the body or scalp.
• Athlete's foot – which affects the skin on the feet, causing it to become red, flaky and itchy.
• Fungal nail infection – which causes the toenails or fingernails to become thickened, discoloured and sometimes brittle, with pieces of nail breaking off.
• Vaginal thrush – which causes irritation and swelling of the vagina and vulva.
• Some kinds of severe dandruff caused by fungi – which causes flakes of skin to peel on the head

Invasive fungal infections

Invasive fungal infections are less common but more serious. They are infections that occur deep inside the body's tissue or in one of the internal organs. Invasive fungal infections can affect the:

• Lungs – for example, aspergillosis, where a fungus called aspergillus infects the lining of the lungs.
• Brain – for example, fungal meningitis, where a fungus infects the protective membranes surrounding the brain and spinal cord.
• People with a weakened immune system are particularly vulnerable to invasive fungal infections. Those at risk include:
  • People with HIV and AIDS.
  • People having high-dose chemotherapy to treat cancer.
  • People who are taking medicines to suppress the immune system, such as corticosteroids; in particular, people who have had an organ transplant will be taking immune suppressants, making them more susceptible to fungal infections.

How antifungal medicines work

Antifungal medicines work by either:

• Killing the fungal cells – for example, by affecting a substance in the cell walls, causing the contents of the fungal cells to leak out and the cells to die.
• Preventing the fungal cells from growing and reproducing.

Types of antifungal medicines

Antifungal medicines are used in several ways, depending on your specific fungal infection. The main types of antifungal medicines include:

• Topical antifungals – applied directly to the skin, hair or nails.
• Oral antifungals – which are swallowed in capsule, pill or liquid form.
• Intravenous antifungals – which are injected into your bloodstream.
• Intravaginal antifungal pessaries – small, soft tablets inserted into the vagina to treat conditions such as vaginal thrush.

Commonly used antifungal medicines

There are many different types of antifungal medicines, and you may be familiar with some of the popular brand names. Many of these brands will contain the same generic antifungal ingredients (alone or in combination). Some of the most common include:

• clotrimazole
• econazole
• miconazole
• tolnaftate
• fluconazole
• ketoconazole
• amphotericin

The package should say which antifungal medicine the product contains. It should also say how strong the antifungal medicine is, usually shown as a percentage of the product or in milligrams, for example, "Ointment containing 1% clotrimazole" or "capsules containing 50mg of fluconazole".

Getting the right dose of antifungal treatment

Your doctor or pharmacist should advise on how to take or use your antifungal medicine. The patient information leaflet that comes with your medicine will also contain advice on using your medicine.

Speak to your doctor or pharmacist if you take too much of your antifungal medicine. You may be advised to visit your nearest hospital's accident and emergency department.

If you are advised to go to hospital, take the medicine's package with you so the healthcare professionals who treat you know what you have taken.

Antifungal medicines for children

Some antifungal medicines can be used on children and babies. For example, miconazole oral gel can be used to treat oral thrush in babies.

Check the patient information leaflet that comes with your medicine to see if it's suitable for children, or ask your pharmacy. Different doses are usually needed for children of different ages.

Unnecessary or prolonged use of antifungal medications can diminish sensitivity of fungi to medication. Therefore ensure that you are taking the correct anti fungal agent in appropriate dose.

Details of two popular antifungal medications tolnaftate and clotrimazole are given below:

Tolnaftate

Tolnaftate belongs to antifungal group of medicines. It is used to treat certain kinds of fungal infections. It is available over the counter. It is available under various brand names such as Absorbine Jr and Tinactin. It is a synthetic thiocarbomate (1).

This product can be purchased at your medical store in the following forms:

• Ointment
• Spray
• Cream
• Lotion
• Gel/Jelly
• Powder
• Solution

Medical uses of Tolnaftate

It is used to treat fungal conditions such as (2):

Jock itch

It is a fungal infection of the groin region which may occur in any gender but is more common among males.

Culprits behind this infection are usually Trichophyton rubrum, Candida albicans and Epidermophyton floccosum.

Signs and symptoms

As can be garnered from the common name of this infection, it causes itching or a burning sensation in the groin area, thigh skin folds or anus. It may also include inner thighs and genital areas, as well as spreading back to the perineum and perianal areas.

Jock itch is often painful or itchy, but not in every case. There are visual symptoms to help identify a fungal infection. These include:

• Inflammation of the groin, anal area and upper thigh - not including the genitals themselves
• Slightly raised patch
• Sharp borders
• Expanding or spreading, with clearing in the center
• Dry or scaly blisters (occasionally oozing or crusting)
• Abnormally dark or light skin
• Skin redness or inflammation

Fungal infections often pan out in a circle, leaving normal-looking skin in the middle. At the leading edge of the infection the skin is raised, reddish and scaly.

Infected region appears red, tan, or brown, with flaking, rippling, peeling or cracking skin.

The acute infection begins with an area in the groin fold about a half-inch across, usually on both sides. The area may enlarge, and sores may develop. The rash has sharply defined borders that may blister and ooze.

Causes

It is frequently caused by opportunistic infections which are a result of diminished immune system. Fungus in an athlete’s foot infection can spread to groin region through tight restrictive clothing such as jockstraps that trap heat and moisture and provide ideal environment for fungus to flourish.

Athlete’s foot

Athlete’s foot, a fungal infection as known as ringworm of the foot, tinea pedum and moccasin foot, is a widespread and contagious fungal skin condition. It causes itching, blistering and flaking of affected areas. It affects about 15% of population globally.

It is caused by fungus known as Epidermophyton floccosum or molds of the Trichophyton group of fungi, including T. rubrum ,T. mentagrophytes and T. tonsurans (more frequent in children). These parasitic fungi are in general transmitted in moist communal areas where people go barefoot, such as around swimming pools or in locker rooms, and need a warm moist environment like the inside of a shoe to fester.

Fungal infection of the foot may be caused in many ways, such as by walking in an infected locker room, by using an infested bathtub, by sharing a towel used by someone with the disease, by touching the feet with infected fingers such as after scratching feet, or by wearing fungus-contaminated socks or shoes. The fungi may spread to other areas of the body, such as by scratching. The fungi tend to infect areas of skin that are kept warm and moist, such as with clothing insulation, body heat, and sweat. However, the extent of the infection is not limited to only skin. Toe nails become infected with fungi in the same way as the rest of the foot, typically by being trapped with fungi in the warm, dark and moist inside of a shoe.

Infection can usually be avoided by keeping the feet dry by limiting the use of footwear that enclose the feet, or by remaining barefoot.

To treat athlete's foot, it is necessary to prevent its spreading back to the feet by treating the entire infection, wherever it is on the body, until the fungus has disappeared and the skin has fully healed.

Signs and symptoms

Athlete's foot is divided into four categories or presentations:

• Chronic interdigital athlete's foot in which area between toes or digits is most affected.
• Plantar athlete's foot (also known as "moccasin foot") in which soles of feet are most affected.
• Acute ulcerative tinea pedis
• Vesiculobullous athlete's foot.

It manifests in form of vesicles and blisters that secrete mucus.

Athlete's foot appears most often between the toes, with the space between the fourth and fifth digits most commonly afflicted. Cases of interdigital athlete's foot caused by Trichophyton rubrum may be symptomless, it may itch, or the skin between the toes may appear red or ulcerative with scales.

An acute ulcerative type of interdigital athlete's foot caused by T. mentagrophytes is characterized by pain, maceration of the skin, erosions and fissuring of the skin, crusting, and an unpleasant smell due to bacterial infection of the skin.

Plantar athlete's foot (moccasin foot) is also caused by T. rubrum in which there is redness of skin on sole of foot often covered by fine, powdery scales.

The vesiculobullous type of athlete's foot is less widespread and is usually caused by T. mentagrophytes and is distinguished by a sudden eruption of itchy blisters and vesicles on an erythematous base, usually appearing on the sole of the foot.

Ringworm

Ringworm is a skin condition caused by fungal infection of the skin.

The fungi that cause parasitic infection called as dermatophytes, thrive on keratin, the substance found in the outer layer of skin, hair, and nails. These fungi flourish on warm and moist skin, but may also survive directly on the outsides of hair shafts or in their interiors.

Currently, up to 20% of the population may be infected by dermatophytes around the world. It is especially common among people who play sports involving skin-to-skin contact, wrestling in particular. Wrestlers with ringworm may be withheld from competition until their skin condition is declared non contagious by the proper medical authorities.

Signs and symptoms

Signs and symptoms of ringworm fungal infection are:

• Red, scaly, itchy or raised patches.
• Patches may be redder on outside edges or resembles a ring.
• Patches that begins to ooze or develop blister.
• Bald patches may develop, when the scalp is affected.
• On nail it may be thicker discolored or begin to crack.

Mechanism of action of Tolnaftate

Tolnaftate is a topical fungicide. Though its exact mechanism of action is unknown, it is generally believed to prevent ergosterol biosynthesis by inhibiting activity of squalene epoxidase enzyme. Ergosterol is an essential component of yeast and other fungal cell membranes without which they cannot persist, serving many of the same functions that cholesterol serves in animal cells.

Because many fungi and protozoa cannot survive without ergosterol, the enzymes that create it have become important targets for drug discovery. Squalene monooxygenase (also known as squalene epoxidase) is an enzyme that uses NADPH and molecular oxygen to oxidize squalene to 2,3-oxidosqualene (squalene epoxide). Squalene epoxidase catalyzes the first oxygenation step in sterol biosynthesis and is thought to be one of the rate-limiting enzymes in this pathway.

By blocking activity of this enzyme, tolnaftate prevents growth and further reproduction of infective agents.

Tolnaftate has also been reported to distort the hyphae and to block and stunt growth of fungal mycelium in susceptible organisms.

Side effects

Adverse effects of using tolnaftate are as follows (3):

• Irritation of treated area
• Rash
• Itching
• Swelling

Precautions when using tolnaftate

Some medical conditions may interact with tolnaftate cream. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

• If you are pregnant, planning to become pregnant, or are breast-feeding.
• If you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement.
• If you have allergies to medicines, foods, or other substances.

Some drugs may also interact with tolnaftate cream.

Because little, if any, of tolnaftate cream is absorbed into the blood, the risk of it interacting with another medicine is quite low.

Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they act exactly the same way they do in younger adults or if they cause different side effects or problems in older people. There is no specific information comparing use of tolnaftate in the elderly with use in other age groups. However, tolnaftate is not safe for use for chidren.

Although certain medicines should not be used together at all, in other cases it may be necessary to use different medicines together even if an interaction might occur. In these cases, your doctor may want to adjust the dose, or other precautions may be necessary. Tell your healthcare professional if you are taking any other prescription or nonprescription medicines.

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of tolnafate with food, alcohol, or tobacco.

How to use tolnaftate

Use tolnaftate cream exactly as directed by your doctor. Check the label on the medicine for complete medicine instructions.

Tolnaftate cream is for topical use on the skin only.

Shake well before each use.

Clean the affected area with soap and water and dry thoroughly. Apply enough medicine to cover the affected area. Rub in gently. Do not cover unless directed otherwise by your doctor.

Wash your hands immediately after using tolnaftate cream, unless your hands are part of the treated area.

Do not get tolnaftate cream in your eyes, nose, or mouth.

For treating athlete's foot, wear well-fitting, open shoes and change shoes and socks at least once per day.

To clear up your infection completely, continue using tolnaftate cream for the full course of treatment. Do not miss any doses.

Tolnaftate cream may be toxic if swallowed. If you or someone you know may have taken tolnaftate cream by mouth, contact your local poison control center or emergency room immediately.

It is important to use tolnaftate cream for the full course of treatment. Failure to do so may decrease the effectiveness of tolnaftate cream and may increase the risk that the fungus will no longer be sensitive to tolnaftate cream and will not be able to be treated by this or certain other antifungal in the future.

Tolnaftate cream is not recommended for use in children younger than 2 years of age unless directed by a doctor. Safety and effectiveness in this age group have not been confirmed.

If you miss a dose of tolnaftate cream, use it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule.

Clotrimazole

Clotrimazole is an antifungal agent. It is available in market under brand names of Lotrimin, Lotrisone and Mycelex. It is listed among World Health Organization’s list of medicines essential for a basic health care setup (4, 5).

Medical uses of clotrimazole

It is used to treat following skin conditions:

• Ringworm
• Athlete’s foot
• Jock itch
• Vaginal thrush or candidiasis

Vaginal yeast infections are due to excessive growth of Candida. These yeast are normally present in the vagina in small numbers. It is not classified as a sexually transmitted infection; however, it is more frequent among those who are more sexually active.

Risk is elevated by taking antibiotics, pregnancy, diabetes, and HIV/AIDS. Eating a diet high in simple sugar may also be a causative factor. Tight clothing, type of underwear, and personal hygiene do not appear to be factors. Diagnosis is by testing a sample of vaginal discharge. As symptoms are similar to that of the sexually transmitted infections, chlamydia and gonorrhea, testing may be recommended.

Signs and symptoms

The symptoms of vaginal thrush include vulval itching, vulval soreness and irritation, pain or discomfort during sexual intercourse, pain or discomfort during urination and vaginal discharge, which is usually odourless. This can be thin and watery, or thick and white.

Besides above symptoms of thrush, vulvovaginal inflammation can also be present. The signs of vulvovaginal inflammation include redness of the vagina and vulva, fissuring and cracked skin, edematous swelling and painful lesions.

Oral thrush

It is a type of candidiasis or thrush that occurs in mouth or oral cavity. Candida albicans is the main causative organism.

Signs and symptoms

• Appearance of lesions
• Burning sensation in mouth
• Metallic, acidic, salty taste in mouth
• Dysphagia or difficulty in swallowing
• Blisters
• Hoarseness of voice

Mechanism of action of clotrimazole

Clotrimazole acts to kill individual Candida or fungal cells by altering the permeability of the fungal cell wall. It binds to phospholipids in the cell membrane and inhibits the biosynthesis of ergosterol and other sterols required for cell membrane production. This leads to the cell's death via disruption of cell membrane integrity.

Side effects of clotrimazole

Side effects caused by use of clotrimazole are as follows (6):

Dermatological

• Erythema or redness of skin
• Stinging
• Blistering
• Peeling
• Edema
• Itching
• Burning
• Skin irritation in general
• Contact dermatitis

Genitourinary

• Burning
• Itching
• Cramping
• Pain
• Bleeding
• Vulvular lesions

Allergic reactions

• Rash
• Eruption of skin hives
• Blistering
• Peeling
• Redness
• Stinging

Precautions when using clotrimazole

Before using this medication, tell your doctor or pharmacist if you are allergic to clotrimazole or to other azole antifungals (e.g., ketoconazole) or corticosteroids (e.g., triamcinolone); or if you have any other allergies. The market preparation may contain inactive ingredients, which can cause allergic reactions or other problems.

Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of immune system problems or poor blood circulation.

Caution is advised when using this drug in the elderly because they may be more sensitive to the effects of the drug, especially thinning skin.

Though it is unlikely, this medication may slow down a child's growth if used for a long time. The effect on final adult height is unknown. See the doctor regularly so your child's height can be checked.

During pregnancy, this medication should be used only when clearly needed. It has been known to harm a developing fetus. Discuss the risks and benefits with your doctor.

It is not known whether this drug passes into breast milk when applied to the skin. Similar medications pass into breast milk when taken by mouth. Consult your doctor before breast-feeding.

Some medicines may interact with Clotrimazole Cream. Because little, if any, of Clotrimazole Cream is absorbed into the blood, the risk of it interacting with another medicine is low.

Ask your health care provider if Clotrimazole Cream may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use clotrimazole

Use this medication exactly as it was prescribed for you. Do not use the medication in larger amounts, or use it for longer than recommended by your doctor. Follow the instructions on your prescription label.

This medication comes with patient instructions for safe and effective use.

Follow these directions carefully. Ask your doctor or pharmacist if you have any questions. Wash your hands before and after applying this medicine.

Shake the lotion form of this medication well just before you use it.

Apply a thin layer of the medication and rub it in completely.

Do not cover treated skin areas with a bandage or tight clothing, unless your doctor has told you to.

After applying this antifungal ointment, allow your skin to dry completely before dressing. Wear loose-fitting clothing while you are treating jock itch. If you are treating athlete's foot, wear clean cotton socks and keep your feet as dry as possible.

Do not use clotrimazole for longer than 2 weeks for jock itch or 4 weeks for athlete's foot, unless your doctor has told you to.

It may take up to 1 or 2 weeks of using this medicine before your symptoms improve. For best results, keep using the medication as directed. Talk with your doctor if your groin symptoms do not improve after 1 week, or if your foot symptoms do not improve after 2 weeks of treatment.

Store this medicine at room temperature away from moisture and heat. Keep the tube or bottle capped and tightly closed when not in use. Keep it far away from reach of children.

Tolnaftate vs clotrimazole: the comparison

Clotrimazole and tolnaftate are both anti fungal medications. To pick out the best one for your use it is essential to compare both drugs to analyze which one suits your medical requirements better.

Classification

• Tolnaftate is a synthetic thiocarbomate.
• Clotrimazole is an azole.

Medical uses

• Tolnaftate is only used to treat topical skin conditions such as jock itch and ringworm.
• Clotrimazole is used to treat fungal infections and thrush of oral cavity and vagina too.

For children

• Tolnaftate is not safe for use in children.
• Clotrimazole is deemed safe for use in children by medical experts.

Mechanism of action

• Exact mechanism of action of tolnaftate is unknown. It is not exclusively fungicidal but rather prevents fungal infections.
• Clotrimazole inhibits fungal growth by disintegrating their cell membrane. It is a fungicidal agent.