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Laxatives

Lactulose

(Constulose ®, Kristalose ®) powder, liquid

Lactulose is a laxative prescribed by doctors to treat constipation.

 

It works by drawing extra water into your gut. This makes stool looser and easier to pass. Make sure you drink enough water when you take lactulose.

How do I take this medicine?

To take this medication, follow the instructions on your prescription.

Lactulose comes in liquids or powder.

For the liquid:

  • Follow the instructions on this medicine to measure out a dose.

  • If you want, you can mix the liquid with water, milk, or fruit juice to make it taste better.

For the powder:

  • Mix powder with ½ cup of water, and then drink right away.

How long does it take to work?

Lactulose takes about 24 to 48 hours to start working.

What are the side effects?

The main side effects of this medication are bloating, gas, cramps and diarrhea or loose stools.

Bloating and cramps are usually worse when a person is very constipated. These side effects usually go away after a person has a good-sized bowel movement.

If you have severe belly pain, bloating or diarrhea, talk to your care team. They may suggest a different medication.

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