Do I have seborrheic dermatitis? How can I treat it?

There are many conditions you may be suffering.
If you haven't tried it. You can use an anti-dandruff shampoo (leave the suds on your scalp for at least 5 minutes and do it shampoo again waiting 5 more minutes before rinsing). Do not use Sulfa or salt free shampoos (at all). They will not cleanse deeply compared to antidandruff shampoo. If your hair is short, then you do not need anything else. You can also keep using your ketaconazol shampoo but, I would recommend trying this for a few weeks and seeing how you do 1st.
When styling your hair, avoid any heat tools, and products that contain strong alcohol. Avoid spraying the affected areas with perfume. Use a face-body cleanser that contains benzoyl peroxide. You want to apply that cleanser to all the body areas that over-produce oil. Same idea, leave it for 5-10 minutes before you rinse off with luke warm water or cold water if you tolerate it. Avoid very hot water (it can make your condition worse).
Even when your skin produces excess oil, you still need to hydrate it. If you skip the next step, your skin may compensate what you have removed. Please use a very "light" or gel like moisturizer to the areas you previously cleansed after the shower only.
If your skin still produces excessive oil, You want to apply a cream with 2% Salicylic acid on your back. and affected areas. Retinol is an ingredient you may also want to dive in and add into your routine if nothing else works.

Hello, seborrheic dermatitis is a chronic condition, same as acne, ketoconazole shampoo helps a lot and is the treatment of choice, to avoid reccurence ketoconazole shampoo should be discountinued slowly for example: 2 Times /week for 1 month ) then once a week for a month ) then once every two weeks for 1 month. Over the counter products creams exist and Can help your condition in addition to ketoconazole. Another important point, is that there is a lot of triggers that are responsible of seborrheic dermatitis such as stress, infection.... That's why it IS mandatory to avoid these triggers to maintain a long term remission !

Hi there,
Excessive oil production is not Seborrheic dermatitis. Ketoconazole is usually prescribed for a fungus.
You need to see a Dermatologist and get on the proper medication. You may want to look into Accutane as well. See an expert.

Best of luck!