Generlac (Oral)

Lactulose is used to treat constipation. It helps increase how many bowel movements you have each day and how many days you have bowel movements if you have a history of chronic (long-lasting) constipation.

This medicine is available only with your doctor's prescription.

It is very important that your doctor check your progress after taking this medicine. This will allow your doctor to see if the medicine is working properly.

Call your doctor right away if you have severe diarrhea.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

In deciding to use a medicine, the risks of taking it must be compared to the benefits it may provide. This is a choice you and your doctor will make together. For this medicine, consider the following:

Allergies

Inform your doctor if you have ever had any unusual or allergic reactions to this medicine or any other medicines. Also, let your healthcare professional know if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, carefully read the label or package ingredients.

Pediatric

There have not been appropriate studies on the effects of lactulose in children. Its safety and effectiveness have not been established.

Geriatric

There is no information available on how lactulose affects older patients.

Breast Feeding

There are no adequate studies in women to determine the risk to infants when using this medication while breastfeeding. Consider the potential benefits against the potential risks before using this medication during breastfeeding.

Interactions with Medicines

Some medicines should not be used together at all, while others may be used together even if there is a chance of interaction. In these cases, your doctor may need to adjust the dose or take other precautions. It is especially important for your healthcare professional to know if you are taking any of the medicines listed below while using this medicine. The following interactions have been chosen based on their potential importance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is generally not recommended, but may be necessary in some cases. If both medicines are prescribed together, your doctor may adjust the dose or how often you take one or both medicines.

• Droperidol
• Levomethadyl
• Licorice

Using this medicine with any of the following medicines may increase the risk of certain side effects, but using both may be the best option for you. If both medicines are prescribed together, your doctor may adjust the dose or how often you take one or both medicines.

• Acenocoumarol
• Dicumarol
• Lithium
• Phenprocoumon
• Warfarin

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be taken at the same time as food or certain types of food due to possible interactions. Using alcohol or tobacco with some medicines may also cause interactions. Discuss with your healthcare professional about using your medicine with food, alcohol, or tobacco.

Other Medical Problems

Other medical conditions may affect the use of this medicine. Be sure to inform your doctor if you have any other medical conditions, especially:

• Diabetes—Use with caution. May worsen this condition.

• Low lactose or galactose diet—Should not be used by patients on this diet.

• Medical tests or surgery on your colon or rectum (e.g., colonoscopy, proctoscopy)—Patients undergoing these procedures should have a thorough bowel cleansing with another medicine (e.g., non-fermentable solution).

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

Incidence not known

• Confusion
• decreased urine
• dizziness
• dry mouth
• fainting
• fast or irregular heartbeat
• increased thirst
• irritability
• lightheadedness
• loss of appetite
• mood changes
• muscle pain, cramps, or twitching
• nausea or vomiting
• numbness or tingling in the hands, feet, or lips
• restlessness
• seizures
• severe diarrhea
• swelling of the feet or lower legs
• trouble breathing
• unusual tiredness or weakness

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Incidence not known

• Bloated
• excess air or gas in the stomach or intestines
• full feeling
• passing gas
• stomach or intestinal cramps

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

In the U.S.

• Cholac
• Constilac
• Constulose
• Enulose
• Generlac
• Kristalose

In Canada

• Acilac
• Alpha-Lac
• Cephulac
• Chronulac
• Lactulax
• Pms-Lactulose
• Rhodialax
• Rhodialose

Available Dosage Forms:

• Syrup
• Powder for Solution
• Solution

Therapeutic Class: Laxative, Hyperosmotic

Take this medicine exactly as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.

To use the oral liquid:

• Measure the medicine with a marked measuring spoon, oral syringe, or medicine cup.
• You may mix it with fruit juice, water, or milk.

To use the powder for solution: Mix the entire contents of the packet in half a glass (4 ounces) of water until solution is colorless to a slightly pale yellow color.

It may take 24 to 48 hours before you have a normal bowel movement.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For constipation: For oral dosage form (powder for solution): Adults—10 to 20 grams (g) per day. Your doctor may increase your dose to 40 g per day if needed. Children—Use and dose must be determined by your doctor. For oral dosage form (solution): Adults—15 to 30 milliliters (mL) or 1 to 2 tablespoons per day. Your doctor may increase your dose to 60 mL per day if needed. Children—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

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