What Is Jock Itch?

Overview

Jock itch (also called tinea cruris) is a superficial (i.e. on the surface) fungal infection that affects the groin and inner thigh.¹ Even though it is generally an easily treatable and mild condition, it is contagious, and hence, it is important to avoid the spread of fungal spores from other people, animals, objects, and the soil to. Just as vital is reducing the spread of fungal spores from one place on the body to another by thoroughly washing hands after touching an infected area as well as regularly washing bedding, towels, and clothes.

The groin is susceptible to fungal infection because it harbours a favourable environment for growth. Sweating, macerating, and the groin’s alkaline pH make the environment good for fungi.² Tropical and subtropical developing countries have widespread cases of fungal infections like jock itch. A higher prevalence of fungal infections has also been linked to urbanisation and wearing increasingly tight clothing.³

Causes of jock itch

Jock itch (tinea cruris) is caused by dermatophytes - a type of fungi. Dermatophytes need keratin to survive. It is a protein found in hair, nails, and skin. Fungi use fungal spores to reproduce – those spores can survive for many months on skin, soil, and household objects. The fungal spores begin to grow in hot and humid conditions.

Spores can be spread by:

• Human-human contact
• Human-animal contact
• Human-object contact
• Human-soil contact

It is relatively common for tinea fungal infections (also known as ringworm) to affect the groin and feet areas at the same time. This is because the most common types of fungi responsible for jock itch are the same for athlete’s feet. The infection from the feet is generally passed to the groin when drying oneself with a towel.¹

Signs and symptoms of jock itch

Signs and symptoms:

• Itchiness around the groin area 
• Scaly and flaking skin on inner thighs
• Red-brown sores around the groin area (including blistering or pus-filled sores)
• Irritation/pain may be experienced if the skin is moist for a long time
• Secondary infections can cause inflammation and discomfort ^{2, 4}

Management and treatment for jock itch

Exercise, walking, and wearing tight clothing can make the symptoms of a groin infection worse. Therefore, it may be advisable to avoid these activities.

To prevent the spread of fungal infection:

• Wash and dry the infected areas carefully
• Change underwear daily
• Wash clothes, towels, and bedding regularly
• Wear loose-fitting, cotton clothing around the groin

Most tinea cruris can be treated using over-the-counter antifungal creams, gels, or sprays, but you should speak to a pharmacist for the best advice. Generally, creams are used for scaly, non-oozy lesions, whilst gels are used for oozy, moist lesions. Powder treatments are less effective than the other topical treatment modalities, but they are useful in reducing the moisture at the groin.¹ The treatment plan may involve a daily or twice-a-day application of the antifungal product for two to four weeks, but you should follow the manufacturer’s instructions provided in the leaflet. There is an 80-90% cure rate for patients who complete an appropriate tinea cruris treatment course.^{2, 5} For recurrent cases of tinea cruris, oral medications may be advised, but you should seek a GP’s advice.^2,4

If a groin and foot tinea fungal infection occur together, it is vital to treat both at the same time to avoid recurrent infection.

Diagnosis

Jock itch can usually be diagnosed by a GP based on the patient’s history, the clinical appearance as well as location. A scraping of the skin may be done for laboratory analysis if antifungals do not improve your condition. It is important to distinguish jock itch from other similarly presenting skin conditions, including candidiasis, erythrasma, seborrheic dermatitis, and psoriasis, which can be achieved using microscopy.^{1, 2}

Risk factors

Factors increasing susceptibility to jock itch:^{2, 3, 6}

• Obesity
• Weakened immune system
• History of fungal infections (personal or family)
• Type 1 diabetes
• Very young or very old age
• Atherosclerosis
• Venous insufficiency
• Excessive perspiration
• Heavy clothing
• Bad hygiene
• Lower socioeconomic status
• Athletes, particularly contact sports
• Genetic susceptibility to dermatophytes

Diabetes mellitus, family history of tinea infections, and personal history of cooking food (exposure to hot environment) are associated with an increased likelihood of having a chronic or relapsing tinea condition.^{2, 7}

FAQs

How can I prevent jock itch?

You can prevent jock itch by avoiding catching it or avoid spreading it from other areas of your body (commonly the foot) to the groin. Children should not be kept from school if they have jock itch, but the child should be on treatment, and a teacher should be informed; adults, similarly, should not miss work.

• Treat pets that have ringworm (missing patches of fur is a sign of infection)
• Wash hands after touching an animal or soil
• Treat people with fungal infections
• Avoid sharing personal items with someone who has fungal infections
• Avoid touching your infected areas
• Practice good personal hygiene
• Wear shoes in the gym and swimming pool changing rooms
• Wash clothes, bedding, and towels regularly

How common is jock itch?

Jock itch is four times more common in people assigned male at birth (AMAB) than people assigned female (AFAB) and is most commonly seen in adolescent and adult people AMAB.^{1, 2} 10-20% of all people will have a fungal infection at some point in their life. Developing, tropical countries have more fungal infections than other geographies due to higher humidity and temperatures.^8,9 

Is jock itch contagious?

Yes. The spores of the fungi responsible for jock itch can be transferred through:

• Human-human contact
• Human-animal contact
• Human-object contact
• Human-soil contact

What can I expect if I have jock itch?

Expect red-brown sores around the groin area, including the inner thighs, which may be blistering, oozy, or non-oozy. The rash may be painful and irritating and may get worse when the affected area is experiencing high humidity or moisture for extended periods.

It is a curable condition with a high success rate - treatment options are varied and generally successful.

When should I see a doctor?

See a GP if:

• The condition has not improved within two weeks of treatment with an antifungal medication
• You have a weakened immune system

The GP may prescribe oral antifungal tablets if the jock itch has not improved after two weeks of treatment.

Summary

Jock itch is most commonly seen in people assigned male at birth and it is a fungal condition that affects the groin area, including the inner thighs. It presents red-brown sores, flaky and scaly skin, and itchiness in the affected area. It is treated first-hand with topical antifungal creams, gels, or sprays, which can be purchased from a pharmacy. If the infection is persistent, you should seek a GP’s advice, which may involve undergoing a differential diagnosis, or you may be put on oral antifungals. 

It is important to avoid contact with people, objects, animals, and soil which have fungal spores if you want to prevent getting jock itch. This is because fungal spores are transferred through contact. This is also relevant to an infected person - it is important to wash your hands thoroughly after touching an infected area to prevent it from being transmitted to another area of the body - jock itch and athlete's foot commonly occur at the same time. To reduce the symptoms of jock itch it may be a good idea to avoid exercise and excessive walking, and it is a good idea to wear loose-fitting cotton clothing over the groin areas.