Levine and Rasmussen (1983) evaluated the effectiveness of intralesional injections of corticosteroids in the therapy for nodulo-cystic acne. Triamcinolone acetonide at a concentration of mg/ml was as effective as a higher concentration of mg/ml. Betamethasone phosphate had little, if any, effect on nodulo-cystic acne lesions at concentrations of , , and mg/ml, when compared with saline controls. Mahajan and colleagues (2003) compared the effectiveness of intralesional triamcinolone with that of a combination of intralesional lincomycin and intralesional triamcinolone in nodulo-cystic acne. A total of 10 patients of nodulo-cystic were injected with intralesional triamcinolone acetonide ( mg/ml), while 9 patients were given lincomycin hydrochloride (75 mg/ml) in addition to the intralesional triamcinolone. They were followed-up 48 hours, 1 week and 1 month later. At 1 week, 7 patients (70 %) treated with injection triamcinolone showed 66 % improvement, whereas all 9 (100 %) patients treated with lincomycin and triamcinolone showed 100 % improvement that was stable at 1 month. The authors concluded that c combination of intralesional triamcinolone and lincomycin is superior to intralesional triamcinolone alone in the treatment of nodulo-cystic lesions of acne.