Constilac (Lactulose)

(℞) Prescription Required

Constilac (Lactulose) Dosage and Side Effects

This medication is a laxative used to treat constipation. It may help to increase the number of bowel movements per day and the number of days you have a bowel movement. Lactulose is a colonic acidifier that works by increasing stool water content and softening the stool. It is a man-made sugar solution.

Proper Use of this medication

Take this medication by mouth, usually once daily for constipation, or as directed by your doctor. If you are taking the solution, to improve the taste, you may mix it into fruit juice, water, milk, or a soft dessert. If you are using the crystals in packets, dissolve the contents of the packet in half a glass of water (4 ounces or 120 milliliters), or as directed by your doctor.

Use this medication regularly in order to get the most benefit from it. Remember to take it at the same time each day. Dosage is based on your medical condition and response to therapy.

It may take up to 48 hours to have a bowel movement. Inform your doctor if your condition persists or worsens.

Side Effects

Gas, bloating, burping, stomach rumbling/pain, nausea, and cramps may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if any of these unlikely but serious side effects occur: diarrhea, vomiting, muscle cramps/weakness, irregular heartbeat, mental/mood changes, seizures, severe or persistent stomach/abdominal pain, bloody stools, rectal bleeding.

A very serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction may include: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Warnings and Precautions

Before taking lactulose, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: a low galactose diet (e.g., a diet that includes few or no milk products), certain other bowel problem (bowel obstruction).

Before using this medication, tell your doctor or pharmacist your medical history, especially of: diabetes.

The elderly may be at a greater risk for loss of blood minerals (e.g., potassium, sodium) while using this drug, especially if they are using it for an extended time.

Do not take any other laxative medications while taking this drug. Frequent use or overuse of laxatives can cause a severe loss of body water (dehydration). This is especially likely to occur in children or the elderly. Contact your doctor right away if you develop any of the following symptoms of dehydration: muscle weakness, muscle cramps, dizziness.

Before having surgery or other procedures (e.g., electrocautery), tell your doctor or surgeon that you are using this medication.

This medication contains different sugars. If you have diabetes, this medication may affect your blood sugar. Check your blood sugar regularly as directed and share the results with your doctor. Your doctor may need to adjust your diabetes medication, exercise program, or diet.

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

It is not known whether this drug passes into breast milk. Consult your doctor before breast-feeding.

Interactions with this medication

Your healthcare professionals (e.g., doctor or pharmacist) may already be aware of any possible drug interactions and may be monitoring you for it. Do not start, stop or change the dosage of any medicine before checking with them first.

Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: antacids containing aluminum and/or magnesium, other laxatives.

This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.

Other related products

The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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