Constulose Solution

Generic Name: Lactulose (LAK-tyoo-lose)Brand Name: Constulose

Constulose Solution is used for:

Treating constipation. It may also be used for other conditions as determined by your doctor.

Constulose Solution is a colonic acidifier. It works by drawing water into the colon, which softens the stool and helps to produce a bowel movement.

Do NOT use Constulose Solution if:

  • you are allergic to any ingredient in Constulose Solution
  • you are on a low galactose diet

Contact your doctor or health care provider right away if any of these apply to you.

Before using Constulose Solution:

Some medical conditions may interact with Constulose Solution. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have diabetes, an appendix disease, rectal bleeding, a blockage of the intestinal tract, or a disease called galactosemia

Some MEDICINES MAY INTERACT with Constulose Solution. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Antacids because they may decrease Constulose Solution's effectiveness

This may not be a complete list of all interactions that may occur. Ask your health care provider if Constulose Solution may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use Constulose Solution:

Use Constulose Solution as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Constulose Solution may be mixed with fruit juice, water, or milk. Drink 1 or more 8-ounce glasses of liquid with each dose.
  • A bowel movement should occur 24 to 48 hours after taking Constulose Solution.
  • If you miss a dose of Constulose Solution and you are taking it regularly, take it as soon as possible. If several hours have passed or if it is nearing time for the next dose, do not double the dose to catch up, unless advised by your health care provider. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use Constulose Solution.

Important safety information:

  • Tell your doctor or dentist that you take Constulose Solution before you receive any medical or dental care, emergency care, or surgery.
  • Diabetes patients - Constulose Solution may raise your blood sugar. High blood sugar may make you feel confused, drowsy, or thirsty. It can also make you flush, breathe faster, or have a fruit-like breath odor. If these symptoms occur, tell your doctor right away.
  • LAB TESTS, including blood electrolyte levels, may be performed while you use Constulose Solution. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
  • Use Constulose Solution with caution in the ELDERLY; they may be more sensitive to its effects.
  • PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using Constulose Solution while you are pregnant. It is not known if Constulose Solution is found in breast milk. If you are or will be breast-feeding while you use Constulose Solution, check with your doctor. Discuss any possible risks to your baby.

Possible side effects of Constulose Solution:

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Belching; gas; nausea; stomach cramps; vomiting.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); diarrhea.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. You may also report side effects at

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center (, or emergency room immediately. Symptoms may include diarrhea; stomach cramps.

Proper storage of Constulose Solution:

Store Constulose Solution at room temperature between 68 and 77 degrees F (20 and 25 degrees C). A normal darkening of the solution may occur under normal storage conditions. This will not affect the product. Exposure to temperatures above 86 degrees F (30 degrees C) will cause extreme darkening of the solution. Do not use the medicine if this occurs. Store away from heat, moisture, and light. Do not store in the bathroom. Keep Constulose Solution out of the reach of children and away from pets.

General information:

  • If you have any questions about Constulose Solution, please talk with your doctor, pharmacist, or other health care provider.
  • Constulose Solution is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.

This information is a summary only. It does not contain all information about Constulose Solution. If you have questions about the medicine you are taking or would like more information, check with your doctor, pharmacist, or other health care provider.

  • Constulose Prescribing Information (FDA)
  • Lactulose Detailed Consumer Information (PDR)
  • Lactulose Professional Patient Advice (Wolters Kluwer)
  • Lactulose Prescribing Information (FDA)
  • Enulose Concise Consumer Information (Cerner Multum)
  • Enulose Prescribing Information (FDA)
  • Generlac Prescribing Information (FDA)