Brief Answer:
Acne treatment; visit a dermatologist

Detailed Answer:
Hello. Thanks for writing to us at healthcaremagic

I am Dr. Kakkar. I have gone through your query.

Oily skin is acne prone. In oily skin oil/sebaceous glands are functioning overtime.
Cleansing is an important step in acne prone/oily skin; at the same time it is essential that she does not over dry the skin because that can do more harm than good.
A soap or a face wash is harsh for acne prone skin, because they extract all the moisture from the skin and can over-dry the skin; therefore, the oil glands which are already working overtime, get the signal that the surface is dry and hence they in turn produce more oil to compensate the dryness that you may have caused by a harsh cleanser, this causing rebound oiliness!!
Rather than a soap, I would suggest a gentle cleanser for her e.g cetaphil cleansing lotion, which does'nt over dry and retains natural skin moisture. She may use it twice daily.
There is no need for any moisturizer in oily skin because that might further increase the oiliness.

Acne treatment mainly is centered around Topical antibiotics like clindamycin/nadifloxacin, Topical benzoyl peroxide and Topical retinoids.

For moderately severe or severe acne oral treatment should also be started. Oral treatment includes Antibacterials like doxycycline, minocycline and
Oral Retinoids e.g isotretinoin.

Since acne can reform once you are totally off medications, therefore, it is useful practice to continue with some form of a maintenance regimen, commonly a Topical Retinoid e.g Adapalene, even when acne activity is under control, to prevent formation of new acne lesions.
Topical Retinoids are comedolytic and are ideal for maintenance.

These are all prescription medications (Oral as well as Topicals) and therefore I would suggest that she seeks an appointment with a dermatologist in your region for a proper visual assessment of the severity of her acne and appropriate treatment.

Along with the topical and oral treatment, she may also opt for a few peeling sessions from a dermatologist; salicylic acid peels are very effective for both inflammatory as well as non-inflammatory acne.

Let me know if I can help you further

Regards

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