Q. I have an intensely itchy head with a red rash and white specks on my hair that brush out very easily. I have ruled out lice and wonder what else it could be?
A. Lice can result in a very itchy head and is accompanied with the presence of white nits (lice eggs) on the hair. Your above symptoms may lead someone to believe that is what they are dealing with. In the case of lice, the nits are very difficult to remove and cannot be brushed or combed out very easily.
After ruling out lice, another possibility to consider is you may have dandruff. Dandruff is a condition that causes the skin on your scalp to “flake” which results in the white flecks in the hair. Dandruff is a mild form of seborrheic dermatitis of the scalp. Recall from last week that conditions that end in “itis” are describing inflammation. Derm is another term for skin. Seborrheic refers to areas of the body where there is an abundance of sebaceous glands which secrete sebum, an oil that moisturizes and protects our skin and hair. Thus, seborrheic dermatitis is a condition that causes inflamed, scaly skin and persistent dandruff that affects mainly the scalp but can also be found on the face (around the nose, eyelids, eyebrows, ears), the chest, upper back, under the breasts and in the creases of arms, legs and groin. Though this can be a real nuisance for you, rest assured it is not contagious. That is a relief to know since we have many other contagious ailments we are having to contend with this fall and winter.
Here are some symptoms of seborrheic dermatitis that are found on various body parts;
· Itchiness
· White flakes (dandruff)
· Red, scaly skin
· Yellow, crusty skin as in cradle cap (infants)
· Scaly reddening on edges of eyelids
· Redness in folds of skin
· Inflamed hair follicles on cheeks and upper trunk
· Rash that may appear redder on white skin and darker or lighter on brown or black skin
· A ring-shaped rash
You might be wondering why certain people get this while others do not.
Around 11% of the population have seborrheic dermatitis and it is more common in infants less than three months old (often termed cradle cap)/. in adults aged 30 to 60, in people that have oily skin and those with a family history of psoriasis. It is not fully understood what causes seborrheic dermatitis, but it may be connected to the surplus of oils on our skin. This makes sense when you think about it since our sebaceous glands produce the oils.
It may also be caused by the yeast Malassezia, which we all have on our skin naturally but have an over abundance of it in this condition. This yeast like to feed on the oils we produce from our sebaceous glands. It is also believed that our immune system has a role to play in developing seborrheic dermatitis. Therefore, it shouldn’t come as a surprise to learn that people who have had an organ transplant or have lymphoma or HIV (and thus take immune suppressant medications) are at a higher risk to being affected by this. Also, stress and fatigue are common triggers that may lower your immune system so it is best to those in check.
An interesting find is that conditions that affect the nervous system such as Parkinson’s disease and Epilepsy, among others, can also increase your risk of developing this dermatitis. It is not fully understood why this would be but perhaps disorders that affect the nervous system may also affect the regulating of the sebaceous gland and produce more oils than normal.
A few other factors that increase your risk of developing dandruff are depression, Down Syndrome, or taking certain medications such as lithium, buspirone or chlorpromazine. Keep in mind that having dandruff or a more severe form of seborrheic dermatitis is not a medical concern and certainly does not warrant stopping medications to reduce this risk. Many people find that living in a cold and dry climate, though it doesn’t cause this type of dermatitis, it certainly aggravates it.
Treatment is dependent on the severity of the seborrheic dermatitis. For the milder form that we often term as dandruff, using a mild shampoo can reduce the build-up of oils and skin cells. You may also want to apply a mineral oil or olive oil to the scalp to soften the scales. After leaving the oil on for several hours, comb or brush your hair and then give it a wash. Styling products can aggravate the skin/scalp further so avoid using any hair gels and hair sprays etc.
If this is not sufficient or if your condition is moderate to severe, you can supplement with a medicated treatment once daily but more aptly two or three times a week such as;
· shampoos that contain zinc pyrithione which is both an antibacterial and antifungal agent
· shampoos that contain tar which slows down the rate your skin cells die off and flake (may discolour light coloured hair and make the scalp more sensitive to sunlight)
· shampoos that contain salicylic acid which reduces scaling
· shampoos that contain selenium sulfide which is an antifungal agent (may discolour the hair and scalp)
· shampoos that contain ketoconazole which is an antifungal aimed specifically at reducing the fungi that live on your scalp
· shampoos or lotions that contain a corticosteroid such as hydrocortisone or fluocinolone to reduce the itching, flaking and irritation (may cause thinning of the skin and loss of skin colour)
· creams or lotions that contain calcineurin inhibitors such as tacrolimus or pimecrolimus (less side effects than corticosteroids but has concerns related to possible association with cancers)
Be sure to read the label of your chosen medicated shampoo as some suggest to leave it on for a set number of minutes before getting rinsed off. It is worth noting that it is common for these treatments to lose effectiveness over time and you may need to change your treatment regime. Sometimes these treatments can dry the hair and scalp and you may also want to consider using a conditioner. Once you feel confident that your seborrheic dermatitis is gone, you may want to consider using a medicated shampoo once a week or every two weeks to prevent it from re-occurring.
For more information on this or any other health topic, contact your pharmacist.
