Lactulose

Lactulose is safe to take during pregnancy and won’t harm your baby. If you’re breastfeeding and your doctor or midwife has confirmed your baby is healthy, you can take lactulose safely as it does not pass into breastmilk. If your baby is not feeding as well as usual, or has diarrhoea, you should talk to your health visitor, midwife, pharmacist or doctor.

Typically, lactulose takes around 2 days to start working. If you’re still constipated after 4 or 5 days, we recommend speaking to your doctor for advice. If you take lactulose for liver disease, you might not feel better, but the medicine will help prevent you developing some of the symptoms associated with liver problems.

Lactulose can cause side effects, but most people will usually tolerate the medicine well. A very common side effect of lactulose is diarrhoea, particularly if you take a high dose of the medicine. Other side effects include bloating, wind, feeling sick, being sick and stomach pain. These side effects are typically mild and will usually go away after a couple of days. If you suffer from severe diarrhoea or vomiting for more than a couple of days, and you start to experience muscle cramps or an irregular heartbeat, these could be signs of an electrolyte imbalance and you should seek medical attention immediately.

You can take lactulose with or without food at any time that suits you. When taking lactulose twice a day, it’s typically best to have one dose in the morning and one in the evening, ideally 10-12 hours apart. If you’re regularly taking lactulose and forget to take a dose, do not take an extra dose to make up for a forgotten one. Aim to drink 6 to 8 glasses of water during the day while you're taking lactulose or your constipation may get worse.