Dandruff is believed to be caused by an overgrowth of oil in the hair follicles, or by an overgrowth of certain types of bacteria or fungus on the scalp. Dry scalp can be caused by age, the weather, or a reaction to harsh soaps or shampoos.
In more serious cases, dry scalp may be a symptom of a skin condition such as psoriasis or precancerous lesions called actinic keratoses.
As the causes of dry scalp and dandruff are often different, it’s important to know the signs of each condition and get a proper diagnosis, so you can receive the right treatment.
In this article, you’ll learn more about the differences between dandruff and dry scalp, when to see a doctor for a diagnosis, and the best ways to treat each condition.
Symptoms
The symptoms of dandruff and dry scalp can be similar, and the conditions sometimes overlap. With both, you may experience visible white or yellow flakes that appear in the hair and on the shoulders, along with an itchy scalp, but there are some differences to look for.
Symptoms of dandruff include:
White or yellowish flakes that appear in the hair and on the shouldersItchy scalp without inflammation or rednessOily skin on the scalp
Symptoms of dry scalp are often similar to symptoms of dry skin elsewhere on the body. This might mean the skin feels tight or looks ashy. Other symptoms of dry scalp include:
ItchinessRedness or inflammationSkin appears scalyCracked skinRough skin
Neither dry scalp nor dandruff is contagious.
Causes
Although dandruff and dry scalp may appear on the scalp in a similar way, the causes behind each condition are different.
Dandruff
Seborrheic dermatitis is the medical term used to describe dandruff. The exact cause of this condition is unknown, but it is believed to be due to a number of factors, including:
Overproduction of skin oil (sebum) in the hair follicles and oil glandsPresence of a type of yeast on the skin called MalasseziaPresence of certain bacteria on the skinStressCold or dry weather in winterCertain hair care products
Dry Scalp
While dry scalp shares some of the same causes as dandruff, there are also different causes.
Dry scalp can be caused by the same factors that cause dry skin in other parts of the body. These include:
A dry environment with low humidity, either in summer or winterOlder ageHarsh soap or shampooLong showers or baths that are hotExposure to heating or air conditioningPrescription drugsHormonal imbalancesGeneticsSkin conditions like psoriasis and eczemaHealth conditions like diabetes or kidney disease
Diagnosis
It can be hard to differentiate between dandruff and dry scalp on your own because the symptoms of each condition are similar. Some dermatologists suggest you try a gentle shampoo or an over-the-counter medicated dandruff shampoo first to see if it reduces your symptoms.
If it doesn’t, then it may be time to consult your doctor. They or a board-certified dermatologist will be able to identify the distinctions between the conditions and make a diagnosis.
Diagnosing dry scalp and dandruff follows the same process. A doctor will:
Take your medical historyAsk about your symptomsDo a physical exam of the skin
Treatment
Dandruff
Treatment for dandruff usually depends on the severity of the condition. For example, mild to moderate dandruff can often be treated with medicated over-the-counter (OTC) dandruff shampoos available at drugstores and supermarkets.
For an effective dandruff shampoo, look for one that contains ingredients like:
Salicylic acidSelenium sulphideZinc pyrithioneKetoconazoleCoal tar
These OTC medicated shampoos are usually meant to be used daily initially. Once your dandruff is under control, these shampoos can often be used just once or twice a week.
If you don’t see improvements after a few weeks, you may want to see your doctor or dermatologist. They may recommend a prescription-grade dandruff shampoo or can make a diagnosis of other skin conditions based on a physical exam.
Dry Scalp
Treatment for dry scalp varies depending on the underlying cause. In most cases, dry scalp can be effectively treated by switching to a non-medicated, gentle shampoo.
If symptoms of dry scalp don’t improve within a few weeks after switching shampoos, you should see your doctor. Depending on your exam and diagnosis, they may recommend other forms of treatment. These may include:
Medicated ointments or creams applied to the scalpMedicated shampooLight therapyScale softeners
Prevention
Dandruff
Doctors still aren’t sure what causes flare-ups of dandruff, so it’s a mystery as to how to prevent dandruff. Fortunately, dandruff can be treated effectively once it appears.
Here are some steps that can be taken that may reduce the risk of dandruff:
Decrease stress. Get enough sleep. Spend a small amount of time in the sun every day. Avoid harsh midday sun. Wash your hair more frequently. Use appropriate products on the scalp that are non-irritating.
Dry Scalp
To avoid dry scalp:
Take short showers or baths. Switch hot water in the shower or bath to warm water. Use a gentle, non-medicated shampoo. Use a humidifier in the home to increase moisture in the air. Apply ointments to the scalp if prescribed by a doctor. Try not to rub or scratch the scalp. Wear a hat in winter, but avoid a hat that makes the scalp itch. Stay hydrated.
When to See a Doctor
If you have any concerns about your skin or overall health, it’s always a good idea to speak with your doctor.
Dandruff
You should make an appointment to see your doctor if:
Your scalp is very itchyThe symptoms of dandruff are bad or worseningYou have been using anti-dandruff shampoo for a month but are still experiencing symptomsYour scalp is redYour scalp is swollen
Dry Scalp
In most cases, dry scalp will respond well to switching to a gentle, non-medicated shampoo and some basic lifestyle changes like avoiding long, hot showers.
But you should call your doctor if:
Your scalp is redYour scalp is swollenYour scalp feels warm to the touchYour scalp is painful to touchYou develop a rash on the scalpThe itch on your scalp prevents you from sleeping or going about your daily life
A doctor will be able to examine you and determine if there could be another skin condition that might be causing your symptoms. They will also be able to advise the best treatment option going forward.
A Word From Verywell
Having dry, flaky skin or itching on your scalp can feel embarrassing, but it’s important to remember that neither dandruff nor dry scalp are caused by poor hygiene and in most cases are easily treated.
Though they may look similar on the scalp, there is a difference between dandruff and dry scalp. It is important to differentiate between the two conditions to find the appropriate treatment. A doctor or dermatologist will be able to correctly diagnose whether you have dry scalp or dandruff and point you toward the best solution.
