Some of the mechanisms by which corticosteroids act are by suppressing the immune system, preventing the narrowing of blood vessels, blocking the accumulation of fluid in tissues known as edema, and preventing over-proliferation of skin cells. Corticosteroids are needed to suppress the body’s immune system when the immune system attacks the body’s own healthy cells. Corticosteroids may also act by reducing the body’s ability to produce chemicals that stimulate the painful process of inflammation. Therefore, when used to treat musculoskeletal pain, corticosteroids can ease pain, reduce inflammation, and improve the mobility of the joint.
Weaker topical steroids are utilized for thin- skinned and sensitive areas, especially areas under occlusion, such as the armpit, groin, buttock crease, breast folds. Weaker steroids are used on the face, eyelids, diaper area, perianal skin, and intertrigo of the groin or body folds. Moderate steroids are used for atopic dermatitis , nummular eczema , xerotic eczema , lichen sclerosis et atrophicus of the vulva , scabies (after scabiecide) and severe dermatitis . Strong steroids are used for psoriasis , lichen planus , discoid lupus , chapped feet, lichen simplex chronicus , severe poison ivy exposure, alopecia areata , nummular eczema, and severe atopic dermatitis in adults. 
Selective serotonin reuptake inhibitors (SSRIs) transfer into breast milk to varying extents. Paroxetine is reported to have the lowest transfer into breast milk (weight-adjusted infant dose 1-3%). Fluoxetine transfers to a greater extent (weight-adjusted infant dose ≤ 14%) and its active metabolite, norfluoxetine, has a long half-life of one to two weeks and may accumulate in a breastfed infant. Data on citalopram (weight-adjusted infant dose approximately 5%) suggest that the relative infant dose of citalopram is intermediate between paroxetine and fluoxetine. Based on these data, paroxetine is the preferred SSRI in breastfeeding women.