Someone can have many reasons for acne such as androgenic shift, adrenal fatigue, intestinal dysbiosis, food allergies etc etc.
The way to investigate the causative factor is first of all to assess your hormonal balance. There are numerous tests available for that as well as numerous therapies.
I had very 'stubborn' acne case in my practice with 25 y.o. woman who's skin was perfectly clear three years ago, before she was engaged in very stressful occupation. Leading such stressful life style eventually caused her adrenal fatigue resulting in lack of cortisol in the body with subsequent liver toxicity etc. Many things were tried including Oxytetracycline from dermatologist (which provided only temporary improvement), then Azelaic Acid cream (available in the U.K. only on prescription, but over-the-counter elsewhere in continental Europe), Vitamin B9 which supposed to recover adrenal function - all without significant improvement.
What produced the miracle cure is Electrical Neurostimulation on the skin area of adrenal glands' projection using Russian Skenar (recently being renamed into Diadens) device: three sessions only were sufficient to rid of the acne completely.
I would emphasise on the need to investigate the cause before you proceed with any treatment (that is to make the treatment cost-effective).
Most homotoxicologists run diagnostic tests on their patients before prescribing any treatment; these tests could be either non-invasive EAV, Bioresonance, Health Detector etc. and/or conventional blood, saliva, stool or urine tests... Some of the homotoxicologists can provide Skenar treatment as well as prescription for anti-homotoxic medication and advice on nutrition and life style. Try to search for nearest homotoxicologist on ICM website:
http://www.i-c-m.org.uk/search-practitioners?division=11&country=&postcode=&radius=10&page=4
Hope this information helps.
With best wishes,
Alla Cranham, MSc ABMT,
Registered Homotoxicologist
Mercury House
Northgate
Nottingham
NG7 7FN
Tel +44(0) 845 450 7316
Mob +44(0) 77361 47458
Fax +44(0) 115 9163109
http://www.in-vivo-health.co.uk