Is there a pill or tea I can take to make more milk?
Your baby is perfectly capable of building your milk supply. If you suspect you’re experiencing a low milk supply, contact an IBCLC to help you investigate and resolve the underlying cause. Most of the time, correcting the latch along with any or some of the following will improve your milk supply:

Allowing the baby unrestricted access to the breast
Increasing the amount of time baby is nursing
Offering both breasts at every feeding session
Increasing the numbers of feedings
Pumping sessions.

The plan of care will depend on the reason behind why your supply is low. If there is a need for a galactogogue (a substance that promotes lactation in humans and other animals–Wikipedia), it should be used under the supervised care of your primary care provider and IBCLC. Talk to them about dosages, frequency of intake and possible side effects. Remember that the galactogogue will not do the work without you. Even if you are taking a galactogogue, your milk needs to be removed from the breast in order for it to continue making milk. If the milk is not removed, the effect of the galactogogue will not be seen.

Common pharmaceutical galactogogues are:

Metoclopramide (Reglan™): It is available in the US under a doctor’s prescription. This is a medication for gastroesophageal reflux. It increases prolactin levels, causing an increase in breastmilk production. It can cause restlessness, drowsiness, fatigue, depression and involuntary body movements, especially when used longer than two to four weeks. If you feel you are experiencing postpartum depression, this is not the best galactogogue to use.

Domperidone (Motilium): This is a medication used for gastrointestinal disorders. This is prescribed as off label use. Like Metoclopramide, it increases milk production as a consequence of an increase in prolactin levels. It’s considered a safe drug for lactating women; however, it is not available in the US. There are some compounding pharmacies that will make it if there is a doctor’s prescription. A few women may experience abdominal cramping, dry mouth or headaches.

Herbal teas, capsules and tinctures

It’s very important to read the instructions regarding when and how to take a certain herb. There are some herbs that are completely benign no matter the amount, but there are others that can be toxic in large amounts. Doses will depend on your situation. Supervised care is advised.

The most common ones are Alfalfa, Fenugreek, Goat’s Rue, Nettle, and Shatavari. These are all good purpose galactogogues. Avoid Alfalfa if you suffer from Lupus or any other autoimmune disorder.

Stopping the galactogogue will depend on your situation and the cause of your low milk supply in the first place. While some mothers can reduce its use upon reaching a full milk supply, others may have to use it for months or for the whole duration of breastfeeding.

Reference:
West D, Marrasco L. The Breastfeeding Mother’s Guide to Making More Milk, McGraw Hill, 2009, 171-91