Antidepressants and Nursing

by Alan Greene, MD, FAAP

More women become depressed while their children are babies than at any other time in life (Clin Pharmacokinet 1994 Oct;27(4):270-89). With the surging tide of postpartum hormones, mounting sleep deprivation, persistent noise, shifting body image, the change of life structure, and the loss of control of one's own time, this depression is not surprising -- even with a brand-new bundle of joy in the home.

For a nursing mother, making the decision to take medicine to treat this depression is tricky. We know some medicines are not safe to take when nursing; others are okay. For most medicines, there is not enough known to do better than make an educated guess. Most of the antidepressants fall into this last category.

Since most medications of any kind taken by the mother do show up in the breast milk, my rule of thumb is that, all other things being equal, it is better for a nursing mom not to take a medicine that is not clearly okay to prescribe for the baby.

With Depression, All Other Things Aren't Equal

Solid evidence is mounting that maternal depression is not good for babies' development. A study released just last month looked at 225 four-month-old infants, and their responses to the voices of depressed and non-depressed women. Babies do not learn as well when they are listening to the flatter, less melodic voices of depressed women. Adults' perky, high-pitched baby talk sets the stage for intellectual development (Child Development 1999;70:560-570).

Depressed mothers deserve treatment, both for their babies' sakes, and so that the mothers do not miss out on enjoying one of life's unrepeatable joys -- the all-too-brief babyhood of each child.

It's best to treat the depression with sleep, exercise, bright light, upbeat music, and healthy food. Exercise is particularly difficult in the postpartum period -- both time and energy are often lacking. But exercise has been proven to help specifically with postpartum depression (J Sports Med Phys Fitness 1997 Dec;37(4):287-91). Cooperation and commitment will be needed from family and friends to guard Mom's sleep and to free her up for daily aerobic exercise -- outside if possible (Prev Med 1999 Jan;28(1):75-85). An hour of aerobic exercise daily can be as powerful as even the strongest antidepressant medications. Even 10 minutes a day can make a noticeable difference.

Anaerobic exercise, while effective at treating depression, creates lactic acid that causes sore muscles. This lactic acid gets into the breast milk. It doesn't taste good and leads to fussier babies -- which in turn increases the risk of depressed moms (Pediatrics 1992 Jun;89(6 Pt 2):1245-7). I also wonder whether depression itself may alter breast milk, giving another good reason to treat.

Even an hour of quiet rest with no responsibilities can significantly improve the depressed symptoms (J Sports Med Phys Fitness 1997 Dec;37(4):287-91). If treating the depression without medicines isn't satisfactory, I am in favor of using antidepressant medicines.

Should Mom Discontinue Nursing?

We know that nursing is of tremendous benefit in a great many ways. The magnitude of the value depends partly on the age of the baby. Breast milk is much more important for a 3-month-old than for a 13-month old.

What do we know of the hazards of antidepressants? The use of antidepressant medications during nursing has not been systematically investigated. The medical literature is peppered with case reports and small, uncontrolled studies. These publications span over three decades, but the largest single study by one group of investigators examined 12 mother-infant pairs (J Clin Psychiatry 1998;59 Suppl 2:41-52). There is not enough information to make firm guidelines, but there is enough to reach educated opinions.

We do know that while all antidepressant medicines show up in the breast milk the babies drink, the different medications are excreted into breast milk in different amounts. In general, the more fat-soluble the drug is, the higher the concentration in breast milk. Other factors, such as the pH of the drug, also make a difference.

The goal is to minimize the amount of antidepressant the baby drinks while maximizing mom's emotional health. Each situation deserves individual consideration.

Bupropion (Wellbutrin) accumulates in human breast milk more than other antidepressants. It is found in concentrations more than twice that found in mom's blood (Ann Pharmacother 1993 Apr;27(4):431-3 ). Buproprion has not been detected in the infant's blood, though, indicating that it accumulates in small amounts there, if at all.

The most popular group of antidepressants are the SSRIs (selective serotonin re-uptake inhibitors). Fluoxetine (Prozac) and citalopram (Celexa) in breast milk give babies a higher dose than the other antidepressants in this class (Br J Clin Pharmacol 1997 Sep;44(3):295-8). Do these higher doses make a difference for babies?

There have only been 5 small studies looking at the effect of fluoxetine (Prozac) on nursing infants. While the organized studies found no measurable effect (Br J Psychiatry 1998 Feb;172:175-8), isolated symptoms have been reported in some nursing infants when mom was taking the drug (Am J Psychiatry 1996 Sep;153(9):1132-7). Perhaps the fluoxetine caused the symptoms.

Crying, sleep disturbance, vomiting, and watery stools began suddenly in one baby after the mother began treatment. The baby was found to have blood levels higher than that found in adults -- on only the second day of feeding. The baby was switched to formula and the symptoms disappeared. When bottled breast milk was tried, the symptoms returned (Am Acad Child Adolesc Psychiatry 1993 Nov;32(6):1253-5 ).

Fluvoxamine (Luvox), paroxetine (Paxil) and sertraline (Zoloft) are present in breast milk, but at lower levels (Br J Clin Pharmacol 1997 Sep;44(3):295-8). They also leave the system quicker than fluoxetine (Prozac).

Some studies have shown that sertraline (Zoloft) could not even be found in breast milk (Am J Psychiatry 1996 Sep;153(9):1132-7). We now know that the drug is present in tiny amounts. The highest concentrations are found in hind-milk (the high-fat milk that follows the initial fore-milk, which contains more water) 7-10 hours after taking the tablet (Am J Psychiatry 1997 Sep;154(9):1255-60). The lowest amounts are found in the hour prior to taking the Zoloft, which is usually a once-a-day medication. Overall, nursing infants receive less than 0.3 percent of mom's dose, even after adjusting for their weight (Br J Clin Pharmacol 1998 May;45(5):453-7 ). No adverse events have been reported. Where studied, developmental milestones have proceeded on course, although one baby has been found who had blood concentrations of Zoloft at half its mother's levels (Am J Psychiatry 1998 May;155(5):690-2).

If you are taking sertraline (Zoloft) and are not nursing often, the best time to nurse is during the hour before taking the pill. If you do need to nurse at the peak period of concentration, nursing for a brief period, and discarding the hind-milk, can also reduce the amount of drug the baby receives. Hind-milk is especially rich in nutrients, so it should not be discarded at other times of the day unless there are other sources of nutrition.

There is more data about the effects of tricyclic antidepressants on breastfeeding (such as nortriptyline (Pamelor) and amitriptyline (Elavil)) than any of the other psychologically active medicines. However, the grand total is only 66 mother-infant pairs studied (J Psychopharmacol 1999;13(1):64-80). The combined medical literature on tricyclic antidepressants has not suggested any solid reason to prevent a mother taking them while breast feeding (J Affect Disord 1997 May;43(3):225-37).

Doxepin should be avoided (Am J Psychiatry 1996 Sep;153(9):1132-7). Apnea and excessive drowsiness have been reported in breast-fed babies whose mothers took the drug (Physician's Desk Reference, 1999 Medical Economics).

Far less is known about the safety or effectiveness of taking St. John's Wort while nursing. Some studies (although not in the postpartum period) do show it to be effective compared to placebo and other antidepressant drugs. Although side effects can occur (most commonly a photo-toxic skin reaction), the side effect profile is better than any other medicine used for depression (Int J Clin Pharmacol Ther 1999 Mar;37(3):111-9). It may prove to be a nice, gentle alternative for nursing moms. At this point, we just don't know.

Postpartum major depression occurs in as many as one of 10 childbearing women. This depression often goes undiagnosed. If left untreated, the depression can have a serious negative impact on the baby's emotional and psychological development, as well as on the mother and her relationship with significant others. Women with postpartum depression often respond very well to treatment, and should be treated (Am Fam Physician 1999 Apr 15;59(8):2247-54, 2259-60). I'm glad your doctor is taking this seriously.

For healthy, full-term babies, the known benefits of breast milk outweigh the potential hazards of most antidepressant medicines. From all that we know, Zoloft is a fine choice. Be sure to get some help with the sleeping problems as well. Soon your daughter will be entering a time of giggles and smiles; she'll be more social than ever before. You should be feeling better just in time to enjoy some of the most magical months of your life.

Dr. Alan GreeneDr. Alan Greene, author of Raising Baby Green and Feeding Baby Greene, is the founder of Dr.Greene.com and the WhiteOut Movement. He is a frequent guest on such shows as Good Morning America, The Today Show, and the Dr. Oz Show. He is on the Board of Directors of Healthy Child Healthy World and The Lunchbox Project. Dr. Greene is a practicing pediatrician at Stanford University's Packard Children's Hospital.

Copyright © Greene Ink, Inc., all rights reserved. Permission to republish granted to Pregnancy.org. Reviewed by Khanh-Van Le-Bucklin M.D. & Liat Simkhay Snyder M.D. August 25, 2009.