Pityriasis Pilaris: Causes, Symptoms and Treatment in the UK

Pityriasis pilaris, medically often referred to as phrynoderma, is a specific type of follicular hyperkeratosis. In plain English, this means a buildup of the protein keratin in the hair follicles, leading to the formation of small, pointed papules or 'plugs'. The name phrynoderma translates from Greek as 'toad skin', which describes the rough, dry, and bumpy texture that the skin adopts.

While it is less common in the UK than atopic eczema or acne, it is a significant dermatological concern because it often serves as a visible marker for internal health, specifically nutritional deficiencies. In the United Kingdom, it may be seen in individuals with malabsorption issues, restrictive diets, or certain metabolic conditions. Unlike common 'chicken skin' (keratosis pilaris), pityriasis pilaris is often more widespread and associated with significant skin dryness (xerosis).

The primary symptom of pityriasis pilaris is the appearance of small, firm, flesh-coloured or slightly darker bumps. These bumps are located exactly where the hair emerges from the skin. Key characteristics include:

• Texture: The skin feels remarkably rough, similar to coarse sandpaper or a grater.
• Location: It most frequently appears on the backs of the elbows, the front of the knees, the buttocks, and the extensor surfaces of the limbs.
• Associated Dryness: The surrounding skin is often very dry and may flake or scale.
• Lack of Itch: Unlike eczema or hives, pityriasis pilaris is rarely itchy or painful, though it can be cosmetically distressing.
• Eye Symptoms: If the cause is Vitamin A deficiency, patients might also notice 'night blindness' or dry eyes.

Vitamin A Deficiency

Historically, phrynoderma was considered a definitive sign of Vitamin A deficiency. Vitamin A is crucial for the normal development of skin cells. Without it, the skin fails to shed dead cells correctly, leading to the blockage of follicles.

Wider Malnutrition

NICE guidance and modern clinical studies suggest that the condition is more complex than a single vitamin deficiency. It is often linked to a lack of Vitamin E, Vitamin B-complex, and essential fatty acids. In the UK, this is rarely due to a lack of food availability but is more commonly associated with:

• Digestive disorders like Coeliac disease or Crohn's disease that hinder nutrient absorption.
• Recovery from bariatric (weight loss) surgery.
• History of chronic alcohol misuse affecting liver storage of vitamins.
• Extremely restrictive or 'fad' diets.

It is very common for patients to confuse these two conditions. While both involve 'plugs' in the hair follicles, there are distinct differences. Keratosis pilaris is an extremely common, often genetic condition that typically starts in childhood and improves with age; it is generally not related to diet. Pityriasis pilaris (phrynoderma) tends to appear more suddenly, the bumps are often larger and pointier, and the skin dryness is more profound. If your 'chicken skin' has suddenly worsened or appeared alongside other symptoms like fatigue or night vision issues, it is important to seek a professional medical opinion rather than assuming it is standard keratosis pilaris.

The management of pityriasis pilaris is two-fold: treating the skin surface and addressing the internal cause. Following NHS principles, treatment typically includes:

1. Nutritional Supplementation

If a deficiency is confirmed via blood tests, a GP may prescribe high-dose Vitamin A or multivitamin supplements. It is essential not to self-prescribe high doses of Vitamin A, as it can be toxic in excess.

2. Topical Keratolitics

To smooth the skin, creams containing urea, salicylic acid, or lactic acid are used. These ingredients help dissolve the keratin plugs. Brands like Eucerin or CeraVe produce over-the-counter options, but stronger concentrations may require a prescription.

3. Emollients

Frequent application of thick, fragrance-free moisturisers is vital to repair the skin barrier and reduce the 'toad skin' appearance.

If you notice a sudden change in your skin texture or the development of rough, follicular bumps, you should speak to a GP online or in person. An online GP consultation is an efficient way to get a professional assessment of your skin via high-quality photos or video call.

You should seek advice if:

• The rash is spreading rapidly across your body.
• The skin is becoming cracked, sore, or showing signs of infection.
• You have recently changed your diet or have a known malabsorption condition.
• You are experiencing other symptoms like blurred vision in low light.

Our online doctors can review your clinical history, provide a provisional diagnosis, and suggest the most appropriate topical treatments or refer you for further blood tests if a nutritional deficiency is suspected.