Side effects of domperidone
As with all medications, side effects are possible, and many have been reported with domperidone (textbooks often list any side effect ever reported, but symptoms reported are not necessarily due to the drug a person is taking). There is no such thing as a 100% safe drug. However, our clinical experience has been that side effects in the mother are extremely uncommon, except for increasing milk supply. Some side effects which mothers we have treated have reported (very uncommonly, incidentally):
The amount that gets into the milk is so tiny that side effects in the baby should not be expected. Mothers have not reported any to us, in many years of use. Certainly the amount the baby gets through the milk is a tiny percentage of what babies would get if being treated for spitting up.
Are there long term concerns about the use of domperidone?
The manufacturer states in its literature that chronic treatment with domperidone in rodents has resulted in increased numbers of breast tumours in the rodents. The literature goes on to state that this has never been documented in humans. Note that toxicity studies of medication usually require treatment with huge doses over periods of time involving most or all of the animal's lifetime. Note also that not breastfeeding increases the risk of breast cancer, and breast cancer risk decreases the longer you breastfeed.
Using Domperidone
Generally, we start domperidone at 20 milligrammes (two 10 mg tablets) four times a day. Printouts from the pharmacy often suggest taking domperidone 30 minutes before eating, but that is because of its use for digestive intolerance. You can take the domperidone about every 6 hours, when it is convenient (there is no need to wake up to keep to a 6 hour schedule—it does not make any difference). Most mothers take the domperidone for 3 to 8 weeks. Mothers who are nursing adopted babies may have to take the drug much longer.
After starting domperidone, it may take three or four days before you notice any effect, though sometimes mothers notice an effect within 24 hours. It appears to take two to three weeks to get a maximum effect.
After you have used domperidone for two weeks, we ask you to call (416) 813-5757 (option 3) and ask for a return call. Based on your information, a decision will be made what to do next. If you have unexplained symptoms at any time call the same number immediately.
by Jack Newman, MD, FRCPC
