Transdermal patches (adhesive patches placed on the skin) may also be used to deliver a steady dose through the skin and into the bloodstream. Testosterone-containing creams and gels that are applied daily to the skin are also available, but absorption is inefficient (roughly 10%, varying between individuals) and these treatments tend to be more expensive. Individuals who are especially physically active and/or bathe often may not be good candidates, since the medication can be washed off and may take up to six hours to be fully absorbed. There is also the risk that an intimate partner or child may come in contact with the application site and inadvertently dose himself or herself; children and women are highly sensitive to testosterone and can suffer unintended masculinization and health effects, even from small doses. Injection is the most common method used by individuals administering AAS for non-medical purposes. 
The rationale for the use of vitamin D derivatives in the treatment of psoriasis is based on the observation that patients with hypocalcemia often develop various forms of psoriasis, most notably the pustular form. In one case, a patient who had undergone thyroidectomy developed repeated flares of pustular psoriasis after decreases were made in her dosage of ergocalciferol (Vitamin D 2 ); each episode was related to severe hypocalcemia and resolved after her serum calcium levels normalized. 14 Another patient with osteoporosis experienced dramatic improvement in severe psoriasis after receiving an oral form of vitamin D. 15 This finding, along with the discovery that the bioactive form of 1,25-dihydroxycholecalciferol has been shown to inhibit keratinocyte proliferation and promote keratinocyte differentiation, 16 has led to the development of vitamin D analogs for the treatment of psoriasis.
Occlusive Dressing Technique
Occlusive dressings may be used for the management of psoriasis or other recalcitrant rub a small amount of cream into the lesion until it disappears. Reapply the preparation leaving a thin coating on the lesion, cover with pliable nonporous film, and seal the edges. If needed, additional moisture may be provided by covering the lesion with a dampened clean cotton cloth before the nonporous film is applied or by briefly wetting the affected area with water immediately prior to applying the medication. The frequency of changing dressings is best determined on an individual basis. It may be convenient to apply Triamcinolone acetonide cream under an occlusive dressing in the evening and to remove the dressing in the morning (., 12-hour occlusion). When utilizing the12-hour occlusion regimen, additional cream should be applied, without occlusion, during the day. Reapplication is essential at each dressing change. If an infection develops, the use of occlusive dressings should be discontinued and appropriate antimicrobial therapy instituted.