Pubic Lice (Crabs): Symptoms, Causes, and Effective Treatment in the UK

Pubic lice, commonly known as 'crabs' due to their appearance under a microscope, are small parasitic insects (Pthirus pubis) that live on coarse human body hair. While they are most frequently found in the pubic region, they can also inhabit chest hair, armpits, beards, and even eyelashes or eyebrows.

In the UK, pubic lice are considered a common issue managed by sexual health services and GPs. Unlike head lice, they are primarily transmitted through close bodily contact, most often during sexual activity. It is important to note that having pubic lice is not a reflection of personal hygiene; they are simply a parasite looking for a host. They do not jump or fly, but crawl from one person to another.

The most distinctive symptom of pubic lice is intense itching in the affected area. This itching is an allergic reaction to the saliva of the lice, which they inject into the skin when feeding on blood. The itching is typically more severe at night when the lice are most active.

Other signs you may notice include:

• Visible lice: Small, pale-grey or brown specks attached to hairs.
• Nits: Tiny white or translucent egg sacs glued to the base of the hair shafts.
• Blue spots: Small, pale blueish marks on the skin caused by the lice bites.
• Blood spots: Tiny specks of blood on your underwear.
• Inflammation: Redness or irritation from scratching, which can lead to secondary bacterial infections.

According to NHS guidance, pubic lice are most commonly spread through sexual contact. However, they can also be passed on through other forms of close bodily contact, such as hugging. Although less common, it is possible to catch them by sharing infested items such as:

• Towels
• Bed linen and blankets
• Clothing

They cannot be caught from swimming pools or toilet seats, as they cannot survive for long away from the warmth of the human body and lack the anatomy to grip onto smooth surfaces like plastic or porcelain.

Treatment for pubic lice in the UK is very effective and usually involves the application of insecticide lotions or creams. Common treatments include Permethrin 5% cream or Malatheron lotion. These are often used as follows:

• The treatment is applied to the whole body, focusing on hairy areas (excluding the head/face unless specified).
• It must be left on for the duration specified in the product leaflet (usually 12 hours or overnight).
• A second application is typically required seven days later to kill any lice that have hatched from eggs since the first treatment.

Consistent with NICE (National Institute for Health and Care Excellence) guidelines, it is vital to treat all sexual partners from the last three months simultaneously, even if they do not have symptoms. You should also wash all bedding, towels, and clothes at 60°C or higher to ensure any remaining lice or eggs are destroyed.

Many people feel embarrassed about pubic lice, but they are a routine medical concern for healthcare professionals. Speaking to an online doctor in the UK offers a discreet and confidential way to manage the condition without a face-to-face visit.

You should consider an online GP consultation if:

• Over-the-counter treatments from a pharmacy have not worked.
• You are pregnant or breastfeeding and need advice on which insecticides are safe to use.
• The infestation has spread to your eyelashes or eyebrows, which requires specialist treatment.
• You have developed skin infections from scratching that may require antibiotics.
• You want a confidential referral for a full STI screening.

Our clinicians can provide private prescriptions for stronger treatments and offer evidence-based advice on preventing re-infestation in accordance with UK health standards.

While pubic lice are not an STI in the same way as Chlamydia or Gonorrhoea (as they are parasites, not a bacterial or viral infection), they are often grouped with them because of how they are transmitted. If you have been diagnosed with pubic lice, UK health guidelines recommend a full sexual health check-up to ensure no other underlying infections are present.

To prevent future issues, avoid sharing personal items like towels or clothing with people outside your household and ensure that any new sexual partners are aware if you have recently finished treatment. Routine hygiene does not prevent lice, but early detection through regular self-checks can stop an infestation from spreading.