The postnatal period presents a special problem to healthcare providers treating psychiatric disorders in women. Many new mothers who need antidepressant treatment may wish to breastfeed their infants, but are hesitant to do so for fear of passing on possible harmful effects of the medication through their milk. The focus of this article will be on highlighting and interpreting the existing literature on the benefits and risks to mother and infant of drug treatment for postnatal depression, as well as outlining treatment guidelines for the use of antidepressants in breastfeeding mothers. The article will specifically focus on the use of fluoxetine, sertraline, paroxetine, fluvoxamine and citalopram, which are more commonly used and belong to the selective serotonin reuptake inhibitor group of antidepressants. The tricyclic and other newer antidepressant medications will also be discussed. As there are no published controlled studies on the use of antidepressants by breastfeeding women, publications of individual case reports, case series, and pharmacokinetic investigations serve as the basis for the development of treatment guidelines. Results from this growing body of literature are promising in that, with the exception of a few cases, no serious adverse events have been reported in infants exposed to antidepressant medications through breast milk. In addition nonpharmacological treatments consisting of different types of psychotherapies will be discussed. It is critical that healthcare providers evaluate each mother-infant dyad on an individual basis when faced with the decision to prescribe antidepressant medications during the postnatal period.