Brand Names

Category

• Antacid--Magnesium Hydroxide; Magnesium Oxide
• Antidiarrheal--Polycarbophil; Psyllium Hydrophilic Mucilloid
• Antihyperammonemic--Lactulose
• Antihyperlipidemic--Psyllium Hydrophilic Mucilloid
• Hydrocholeretic--Dehydrocholic Acid
• Laxative, bulk-forming--Malt Soup Extract; Malt Soup Extract and Psyllium; Methylcellulose; Polycarbophil; Psyllium; Psyllium Hydrophilic Mucilloid; Psyllium Hydrophilic Mucilloid and Carboxymethylcellulose
• Laxative, bulk-forming and stimulant--Psyllium and Senna; Psyllium Hydrophilic Mucilloid and Senna; Psyllium Hydrophilic Mucilloid and Sennosides
• Laxative, carbon dioxide-releasing--Potassium Bitartrate and Sodium Bicarbonate
• Laxative, hyperosmotic--Glycerin; Lactulose; Polyethylene Glycol
• Laxative, hyperosmotic and lubricant--Magnesium Hydroxide and Mineral Oil; Mineral Oil and Glycerin
• Laxative, hyperosmotic and stimulant--Magnesium Hydroxide and Cascara Sagrada
• Laxative, hyperosmotic, lubricant, and stimulant--Mineral Oil, Glycerin, and Phenolphthalein
• Laxative, hyperosmotic, saline--Magnesium Citrate; Magnesium Hydroxide; Magnesium Oxide; Magnesium Sulfate; Sodium Phosphate
• Laxative, lubricant--Mineral Oil
• Laxative, lubricant and stimulant--Mineral Oil and Phenolphthalein
• Laxative, stimulant and stool softener (emollient)--Bisacodyl and Docusate; Casanthranol and Docusate; Danthron and Docusate; Dehydrocholic Acid and Docusate; Dehydrocholic Acid, Docusate, and Phenolphthalein; Phenolphthalein and Docusate; Sennosides and Docusate
• Laxative, stimulant or contact--Bisacodyl; Casanthranol; Cascara Sagrada and Phenolphthalein; Cascara Sagrada; Cascara Sagrada and Aloe; Castor Oil; Dehydrocholic Acid; Phenolphthalein; Phenolphthalein and Senna; Senna; Sennosides
• Laxative, stool softener (emollient)--Docusate; Poloxamer 188

Description

Oral laxatives are medicines taken by mouth to encourage bowel movements to relieve constipation.

There are several different types of oral laxatives and they work in different ways. Since directions for use are different for each type, it is important to know which one you are taking. The different types of oral laxatives include:

--

Bulk-formers--Bulk-forming laxatives are not digested but absorb liquid in the intestines and swell to form a soft, bulky stool. The bowel is then stimulated normally by the presence of the bulky mass. Some bulk-forming laxatives, like psyllium and polycarbophil, may be prescribed by your doctor to treat diarrhea.

--

Hyperosmotics--Hyperosmotic laxatives encourage bowel movements by drawing water into the bowel from surrounding body tissues. This provides a soft stool mass and increased bowel action.

There are three types of hyperosmotic laxatives taken by mouth--the saline, the lactulose , and the polymer types. The saline type is often called ``salts.'' They are used for rapid emptying of the lower intestine and bowel. They are not used for long-term or repeated correction of constipation. With smaller doses than those used for the laxative effect, some saline laxatives are used as antacids. The information that follows applies only to their use as laxatives. Sodium phosphate may also be prescribed for other conditions as determined by your doctor.

The lactulose type is a special sugar-like laxative that works the same way as the saline type. However, it produces results much more slowly and is often used for long-term treatment of chronic constipation. Lactulose may sometimes be used in the treatment of certain medical conditions to reduce the amount of ammonia in the blood. It is available only with your doctor's prescription.

The polymer type is a polyglycol (polyethylene glycol), a large molecule that causes water to be retained in the stool; this will soften the stool and increase the number of bowel movements. It is used for short periods of time to treat constipation.

--

Lubricants--Lubricant laxatives, such as mineral oil, taken by mouth encourage bowel movements by coating the bowel and the stool mass with a waterproof film. This keeps moisture in the stool. The stool remains soft and its passage is made easier.

--

Stimulants--Stimulant laxatives, also known as contact laxatives, encourage bowel movements by acting on the intestinal wall. They increase the muscle contractions that move along the stool mass. Stimulant laxatives are a popular type of laxative for self-treatment. However, they also are more likely to cause side effects. One of the stimulant laxatives, dehydrocholic acid, may also be used for treating certain conditions of the biliary tract.

--

Stool softeners (emollients)--Stool softeners encourage bowel movements by helping liquids mix into the stool and prevent dry, hard stool masses. This type of laxative has been said not to cause a bowel movement but instead allows the patient to have a bowel movement without straining.

--

Combinations--There are many products that you can buy for constipation that contain more than one type of laxative. For example, a product may contain both a stool softener and a stimulant laxative. In general, combination products may be more likely to cause side effects because of the multiple ingredients. In addition, they may not offer any advantage over products containing only one type of laxative. If you are taking a combination laxative, make certain you know the proper use and precautions for each of the different ingredients .

Most laxatives (except saline laxatives) may be used to provide relief:

• during pregnancy.
• for a few days after giving birth.
• during preparation for examination or surgery.
• for constipation of bedfast patients.
• for constipation caused by other medicines.
• following surgery when straining should be avoided.
• following a period of poor eating habits or a lack of physical exercise in order to develop normal bowel function (bulk-forming laxatives only).
• for some medical conditions that may be made worse by straining, for example:
  • Heart disease
  • Hemorrhoids
  • Hernia (rupture)
  • High blood pressure (hypertension)
  • History of stroke

Saline laxatives have more limited uses and may be used to provide rapid results:

• during preparation for examination or surgery.
• for elimination of food or drugs from the body in cases of poisoning or overdose.
• for simple constipation that happens on occasion (although another type of laxative may be preferred).
• in supplying a fresh stool sample for diagnosis.

Most laxatives are available without a prescription; however, your doctor may have special instructions for the proper use and dose for your medical condition. They are available in the following dosage forms:

Oral
• Bulk-forming laxatives--
  • Malt Soup Extract
    • Powder (U.S.)
    • Oral solution (U.S.)
    • Tablets (U.S.)
  • Malt Soup Extract and Psyllium
    • Powder (U.S.)
  • Methylcellulose
    • Capsules (U.S.)
    • Granules (U.S.)
    • Powder (U.S.)
    • Oral solution (U.S.)
    • Tablets (U.S.)
  • Polycarbophil
    • Tablets (U.S.)
    • Chewable tablets (U.S. and Canada)
  • Psyllium
    • Caramels (U.S.)
    • Granules (U.S.)
    • Powder (U.S.)
  • Psyllium Hydrophilic Mucilloid
    • Granules (U.S. and Canada)
    • Powder (U.S. and Canada)
    • Effervescent powder (U.S.)
    • For oral suspension (Canada)
    • Wafers (U.S.)
  • Psyllium Hydrophilic Mucilloid and Carboxymethylcellulose
    • Granules (U.S.)
• Bulk-forming and stimulant combinations--
  • Psyllium and Senna
    • Granules (U.S.)
  • Psyllium Hydrophilic Mucilloid and Senna
    • Granules (Canada)
  • Psyllium Hydrophilic Mucilloid and Sennosides
    • Powder (U.S.)
• Hyperosmotic laxative--Lactulose:
  • Lactulose
    • Solution (U.S. and Canada)
• Hyperosmotic laxative--Polyethylene Glycol:
  • Polyethylene glycol 3350
    • Powder (U.S. and Canada)
• Hyperosmotic laxatives--Saline:
  • Magnesium Citrate
    • Oral solution (U.S. and Canada)
  • Magnesium Hydroxide
    • Milk of magnesia (U.S. and Canada)
    • Tablets (U.S. and Canada)
  • Magnesium Oxide
    • Tablets (U.S.)
  • Magnesium Sulfate
    • Crystals (U.S. and Canada)
    • Tablets (U.S.)
  • Sodium Phosphate
    • Effervescent powder (U.S.)
    • Oral solution (U.S. and Canada)
• Hyperosmotic and lubricant combinations--
  • Milk of Magnesia and Mineral Oil
    • Emulsion (U.S. and Canada)
  • Mineral Oil and Glycerin
    • Emulsion (Canada)
• Hyperosmotic, lubricant, and stimulant combination--
  • Mineral Oil, Glycerin, and Phenolphthalein
    • Emulsion (Canada)
• Hyperosmotic and stimulant combination--
  • Milk of Magnesia and Cascara Sagrada
    • Oral Suspension (U.S.)
• Lubricant laxatives--
  • Mineral Oil
    • Oil (U.S. and Canada)
    • Emulsion (U.S. and Canada)
    • Gel (Canada)
    • Oral suspension (U.S.)
• Lubricant and stimulant combinations--
  • Mineral Oil and Phenolphthalein
    • Emulsion (U.S.)
    • Oral suspension (U.S.)
• Stimulant laxatives--
  • Bisacodyl
    • Tablets (U.S. and Canada)
  • Casanthranol
    • Syrup (U.S.)
  • Cascara Sagrada
    • Fluidextract (U.S. and Canada)
    • Tablets (U.S. and Canada)
  • Cascara Sagrada and Aloe
    • Tablets (U.S. and Canada)
  • Cascara Sagrada and Phenolphthalein
    • Tablets (U.S. and Canada)
  • Castor Oil
    • Oil (U.S. and Canada)
    • Emulsion (U.S.)
  • Dehydrocholic Acid
    • Tablets (U.S.)
  • Phenolphthalein
    • Tablets (U.S. and Canada)
    • Chewable tablets (U.S. and Canada)
  • Phenolphthalein and Senna
    • Tablets (Canada)
  • Senna
    • Granules (U.S.)
    • Oral solution (U.S. and Canada)
    • For oral solution (U.S.)
    • Syrup (U.S.)
    • Tablets (U.S. and Canada)
  • Sennosides
    • Granules (U.S. and Canada)
    • Oral solution (Canada)
    • Syrup (U.S. and Canada)
    • Tablets (U.S. and Canada)
• Stimulant and stool softener (emollient) combinations--
  • Bisacodyl and Docusate
    • Tablets (Canada)
  • Casanthranol and Docusate
    • Capsules (U.S. and Canada)
    • Syrup (U.S.)
    • Tablets (U.S.)
  • Danthron and Docusate
    • Capsules (Canada)
    • Tablets (Canada)
  • Dehydrocholic Acid and Docusate
    • Capsules (U.S.)
    • Tablets (U.S.)
  • Dehydrocholic Acid, Docusate, and Phenolphthalein
    • Capsules (U.S.)
  • Phenolphthalein and Docusate
    • Capsules (U.S. and Canada)
    • Tablets (U.S. and Canada)
  • Sennosides and Docusate
    • Tablets (U.S. and Canada)
• Stool softener (emollient) laxatives--
  • Docusate
    • Capsules (U.S. and Canada)
    • Oral solution (U.S. and Canada)
    • Syrup (U.S. and Canada)
    • Tablets (U.S.)
  • Poloxamer 188
    • Capsules (U.S.)

Before Using This Medicine

Importance of diet, fluids, and exercise to prevent constipation--Laxatives are to be used to provide short-term relief only, unless otherwise directed by a doctor. A proper diet containing roughage (whole grain breads and cereals, bran, fruit, and green, leafy vegetables), with 6 to 8 full glasses (8 ounces each) of liquids each day, and daily exercise are most important in maintaining healthy bowel function. Also, for individuals who have problems with constipation, foods such as pastries, puddings, sugar, candy, cake, and cheese may make the constipation worse.

If you are taking this medicine without a prescription, carefully read and follow any precautions on the label. For oral laxatives, the following should be considered:

Allergies--Tell your doctor if you have ever had any unusual or allergic reaction to laxatives. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Diet--Make certain your health care professional knows if you are on any special diet, such as a low-sodium or low-sugar diet. Some laxatives have large amounts of sodium or sugars in them.

Pregnancy--Although laxatives are often used during pregnancy, some types are better than others. Stool softeners (emollient) laxatives and bulk-forming laxatives are probably used most often. If you are using a laxative during pregnancy, remember that:

• Some laxatives (in particular, the bulk-formers) contain a large amount of sodium or sugars, which may have possible unwanted effects such as increasing blood pressure or causing water to be held in the body.
• Saline laxatives containing magnesium, potassium, or phosphates may have to be avoided if your kidney function is not normal.
• Mineral oil is usually not used during pregnancy because of possible unwanted effects on the mother or infant. Mineral oil may interfere with the absorption of nutrients and vitamins in the mother. Also, if taken for a long time during pregnancy, mineral oil may cause severe bleeding in the newborn infant.
• Stimulant laxatives may cause unwanted effects in the expectant mother if improperly used. Castor oil in particular should not be used as it may cause contractions of the womb.

Breast-feeding--Laxatives containing cascara, danthron, and phenolphthalein may pass into the breast milk. Although the amount of laxative in the milk is generally thought to be too small to cause problems in the baby, your doctor should be told if you plan to use such laxatives. Some reports claim that diarrhea has been caused in the infant.

Children--Laxatives should not be given to young children (up to 6 years of age) unless prescribed by their doctor . Since children usually cannot describe their symptoms very well, they should be checked by a doctor before being given a laxative. The child may have a condition that needs other treatment. If so, laxatives will not help, and may even cause unwanted effects or make the condition worse.

Mineral oil should not be given to young children (up to 6 years of age) because a form of pneumonia may be caused by the inhalation of oil droplets into the lungs.

Also, bisacodyl tablets should not be given to children up to 6 years of age because if chewed they may cause stomach irritation.

Older adults--Mineral oil should not be taken by bedridden elderly persons because a form of pneumonia may be caused by the inhalation of oil droplets into the lungs. Also, stimulant laxatives (e.g., bisacodyl, casanthranol, or phenolphthalein), if taken too often, may worsen weakness, lack of coordination, or dizziness and light-headedness.

Polyethylene glycol 3350 should be discontinued if diarrhea occurs, especially in elderly persons in nursing homes.

Other medicines--Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking oral laxatives, it is especially important that your health care professional know if you are taking any of the following:

• Anticoagulants, oral (blood thinners you take by mouth) or
• Digitalis glycosides (heart medicine)--The use of magnesium-containing laxatives may reduce the effects of these medicines

• Ciprofloxacin (e.g., Cipro) or
• Etidronate (e.g., Didronel) or
• Sodium polystyrene sulfonate--Use of magnesium-containing laxatives will keep these medicines from working

• Tetracyclines taken by mouth (medicine for infection)--Use of bulk-forming or magnesium-containing laxatives will keep the tetracycline medicine from working

Other medical problems--The presence of other medical problems may affect the use of oral laxatives. Make sure you tell your doctor if you have any other medical problems, especially:

• Appendicitis (or signs of) or
• Rectal bleeding of unknown cause--These conditions need immediate attention by a doctor

• Colostomy or
• Intestinal blockage or
• Ileostomy--The use of laxatives may create other problems if these conditions are present

• Diabetes mellitus (sugar diabetes)--Diabetic patients should be careful since some laxatives contain large amounts of sugars, such as dextrose, galactose, and/or sucrose

• Heart disease or
• High blood pressure--Some laxatives contain large amounts of sodium, which may make these conditions worse

• Kidney disease--Magnesium and potassium (contained in some laxatives) may build up in the body if kidney disease is present; a serious condition may develop

• Swallowing difficulty--Mineral oil should not be used since it may get into the lungs by accident and cause pneumonia; also, bulk-forming laxatives may get lodged in the esophagus of patients who have difficulty in swallowing

Proper Use of This Medicine

For safe and effective use of your laxative:

• Follow your doctor's instructions if this laxative was prescribed.
• Follow the manufacturer's package directions if you are treating yourself.

With all kinds of laxatives, at least 6 to 8 glasses (8 ounces each) of liquids should be taken each day. This will help make the stool softer.

For patients taking laxatives containing a bulk-forming ingredient :

• Do not try to swallow in the dry form. Take with liquid.
• To allow bulk-forming laxatives to work properly and to prevent intestinal blockage, it is necessary to drink plenty of fluids during their use. Each dose should be taken in or with a full glass (8 ounces) or more of cold water or fruit juice. This will provide enough liquid for the laxative to work properly. A second glass of water or juice by itself is often recommended with each dose for best effect and to avoid side effects.
• When taking a product that contains only a bulk-forming ingredient, results often may be obtained in 12 hours. However, this may not occur for some individuals until after 2 or 3 days.

For patients taking laxatives containing a stool softener (emollient) :

• Liquid forms may be taken in milk or fruit juice to improve flavor.
• When taking a product that contains only a stool softener, results usually occur 1 to 2 days after the first dose. However, this may not occur for some individuals until after 3 to 5 days.

For patients taking laxatives containing a hyperosmotic ingredient :

• Each dose should be taken in or with a full glass (8 ounces) or more of cold water or fruit juice. This will provide enough liquid for the laxative to work properly. A second glass of water or juice by itself is often recommended with each dose for best effect and, in the case of saline laxatives, to prevent you from becoming dehydrated.
• The unpleasant taste produced by some hyperosmotic laxatives may be improved by following each dose with citrus fruit juice or citrus-flavored carbonated beverage.
• Lactulose may not produce laxative results for 24 to 48 hours.
• Polyethylene glycol may not produce laxative results for 2 to 4 days.
• Saline laxatives usually produce results within 1/2 to 3 hours following a dose. When a larger dose is taken on an empty stomach, the results are quicker. When a smaller dose is taken with food, the results are delayed. Therefore, large doses of saline laxatives are usually not taken late in the day on an empty stomach.

For patients taking laxatives containing mineral oil :

• Mineral oil should not be taken within 2 hours of meals because of possible interference with food digestion and absorption of nutrients and vitamins.
• Mineral oil is usually taken at bedtime (but not while lying down) for convenience and because it requires about 6 to 8 hours to produce results.

For patients taking laxatives containing a stimulant ingredient :

• Stimulant laxatives are usually taken on an empty stomach for rapid effect. Results are slowed if taken with food.
• Many stimulant laxatives (but not castor oil) are often taken at bedtime to produce results the next morning (although some may require 24 hours or more).
• Castor oil is not usually taken late in the day because its results occur within 2 to 6 hours.
• The unpleasant taste of castor oil may be improved by chilling in the refrigerator for at least an hour and then stirring the dose into a full glass of cold orange juice just before it is taken. Also, flavored preparations of castor oil are available.
• Bisacodyl tablets are specially coated to allow them to work properly without causing irritation and/or nausea. To protect this coating, do not chew, crush, or take the tablets within an hour of milk or antacids.
• Because of the way phenolphthalein works in the body, a single dose may cause a laxative effect in some people for up to 3 days.

Dosing--There are a large number of laxative products on the market. The dose of laxatives will be different for different products. The number of capsules or tablets or teaspoonfuls of crystals, gel, granules, liquid, or powder that you use; the number of caramels or wafers that you eat; or the number of pieces of gum that you chew depends on the strength of the medicine. Follow your doctor's orders if this medicine was prescribed, or follow the directions on the box if you are buying this medicine without a prescription .

Storage--To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store the capsule, tablet, granules, or powder form of this medicine in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• Keep the liquid form of this medicine from freezing.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

Precautions While Using This Medicine

Do not take any type of laxative :

• if you have signs of appendicitis or inflamed bowel (such as stomach or lower abdominal pain, cramping, bloating, soreness, nausea, or vomiting). Instead, check with your doctor as soon as possible.
• for more than 1 week unless your doctor has prescribed or ordered a special schedule for you. This is true even when you have had no results from the laxative.
• within 2 hours of taking other medicine because the desired effect of the other medicine may be reduced.
• if you do not need it , as for the common cold, ``to clean out your system,'' or as a ``tonic to make you feel better.''
• if you miss a bowel movement for a day or two .
• if you develop a skin rash while taking a laxative or if you had a rash the last time you took it. Instead, check with your doctor.

If you notice a sudden change in bowel habits or function that lasts longer than 2 weeks , or that keeps returning off and on, check with your doctor before using a laxative. This will allow the cause of your problem to be determined before it may become more serious.

The ``laxative habit''--Laxative products are overused by many people. Such a practice often leads to dependence on the laxative action to produce a bowel movement. In severe cases, overuse of some laxatives has caused damage to the nerves, muscles, and tissues of the intestines and bowel. If you have any questions about the use of laxatives, check with your health care professional.

Many laxatives often contain large amounts of sugars, carbohydrates, and sodium. If you are on a low-sugar, low-caloric, or low-sodium diet, check with your health care professional before using a laxative.

For patients taking laxatives containing mineral oil :

• Mineral oil should not be taken often or for long periods of time because:
  • gradual build-up in body tissues may create additional problems.
  • the use of mineral oil may interfere with the body's ability to absorb certain food nutrients and vitamins A, D, E, and K.
• Large doses of mineral oil may cause some leakage from the rectum. The use of absorbent pads or a decrease in dose may be necessary to prevent the soiling of clothing.
• Do not take mineral oil within 2 hours of a stool softener (emollient laxative). The stool softener may increase the amount of mineral oil absorbed.

For patients taking laxatives containing a stimulant ingredient :

• Stimulant laxatives are most often associated with:
  • overuse and the laxative habit.
  • skin rashes.
  • intestinal cramping after dosing (especially if taken on an empty stomach).
  • potassium loss.

Side Effects of This Medicine

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 as soon as possible if any of the following side effects occur:

For bulk-forming-containing

Difficulty in breathing; intestinal blockage; skin rash or itching; swallowing difficulty (feeling of lump in throat)

For hyperosmotic-containing

Confusion; dizziness or light-headedness; irregular heartbeat; muscle cramps; unusual tiredness or weakness

For stimulant-containing

Confusion; irregular heartbeat; muscle cramps; pink to red coloration of alkaline urine and stools (for phenolphthalein only); pink to red, red to violet, or red to brown coloration of alkaline urine (for cascara, danthron, and/or senna only); skin rash; unusual tiredness or weakness; yellow to brown coloration of acid urine (for cascara, phenolphthalein, and/or senna only)

For stool softener (emollient)-containing

Skin rash

Other side effects may occur that usually do not need medical attention. These side effects are less common and may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:

For hyperosmotic-containing

Bloating; cramping; diarrhea; nausea; gas; increased thirst

For lubricant-containing

Skin irritation surrounding rectal area

For stimulant-containing

Belching; cramping; diarrhea; nausea

For stool softener (emollient)-containing

Stomach and/or intestinal cramping; throat irritation (liquid forms only)

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

Additional Information

Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although this use is not included in product labeling, psyllium hydrophilic mucilloid is used in certain patients with high cholesterol (hypercholesterolemia).

For patients taking psyllium hydrophilic mucilloid for high cholesterol :

• Importance of diet--Before prescribing medicine for your condition, your doctor will probably try to control your condition by prescribing a personal diet for you. Such a diet may be low in fats, sugars, and/or cholesterol. Many people are able to control their condition by carefully following their doctor's orders for proper diet and exercise. Medicine is prescribed only when additional help is needed. Follow carefully the special diet your doctor gave you , since the medicine is effective only when a schedule of diet and exercise is properly followed.
• Do not try to swallow the powder form of this medicine in the dry form. Mix with liquid following the directions in the package.
• Remember that this medicine will not cure your cholesterol problem but it will help control it. Therefore, you must continue to take it as directed by your doctor if you expect to lower your cholesterol level.

Other than the above information, there is no additional information relating to proper use, precautions, or side effects for this use.

Revised: 09/29/2000
Interim revision:

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