Acne can appear on any place where there is tendency of excess oil, dead skin and inflammation of hair follicles. Scalp acne is the one which is formed on hair line, behind the neck hair and hair present near ears.
Scalp acne can be caused due to following reasons.
1. Most of the time scalp acne is hereditary and if your parents got these problems then you may also get similar acne problem.
2. Climate change and change of weather in certain areas also increases chance of having scalp acne.
3. Hair may be too much polluted with bacteria so it catches pimples.
4. Too much oil production and oily scalp skin also results into acne formation.
5. Use of shampoos rich in chemicals can also cause acne on scalp.
6. In summers most of people get scalp acne due to excessive exposure in sunlight and heat. This results production of more oil by skin glands eventually forming acne on scalp.
7. Scalp pimples can also formed due to excess of Dihydrotestosterone (DHT) in hair scalp.
8. Inadequate diet and less use of veggies and fruits also result into scalp acne.
9. If you use too much spices in food then you can also become a victim of scalp acne.
10. Use of steroids is detrimental to skin which cause drug toxicity in body.
11. Hormonal imbalance and age factor can also be a reason for pimple growth in scalp as pimple is more seen in pubescent then other ages.
12. Intake of excess caffeine also causes itching on scalp. Avoid taking cold drinks and beverages which have high percentage of caffeine.
Research has shown that too much stress level also boost up oil production, which causes formulation of pustules at scalp. These pustules can also cause further hair fall and other hair diseases.
Poor hygienic condition also leads to formulation of scalp pimples. New hair treatment may also result into reaction in the form of pimple formation.

Read more about Acne Herbal Treatment
Among scalp treatments some of effective home remedies are discussed below:
1. Applying benzoyl peroxide at area of pimples or acne can heal the acne but only complication you can experience is; changing of hair color.
2. Use cotton or wool while applying salicylic acid on the acne area.
3. Herbal anti dandruff shampoos are very effective against scalp pimples.
4. Avoid eating fatty substance and go for more natural products such as fruits and vegetables.
5. Using lemon juice and rose water also helps in reduction of clogged skin. Lemon also makes skin fresh, dry and less oily.
6. Scalp pimple can also be treated by applying orange peel directly to the scalp skin. It will reduce the itching and will make recovery faster.
7. Always keep pillow covers, caps and anything in contact with hair, clean and tidy.
8. Groundnut oil is very effective in healing pimples, pustules or nodules.
9. Tea tree oil is one of most effective home base solutions for any kind of pimples.
Acne must be dealt with amount of care, as it gets more painful the treatment gets difficult day by day.