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Gen Lax (oral and rectal)

Generic Name: bisacodyl (oral and rectal) (bis AK oh dil)
Brand Name: Alophen, Bisac-Evac, Bisco-Lax, Carters Little Pills, Correctol, Doxidan Tablet, Ducodyl, Dulcolax Laxative, Evac-U-Gen, Ex-lax Ultra, Feen-A-Mint, Fleet Bisacodyl, Gen Lax, Magic Bullet, Veracolate

Medically reviewed on October 9, 2017

What is Gen Lax?

Gen Lax is a laxative that stimulates bowel movements.

Gen Lax is used to treat constipation or to empty the bowels before surgery, colonoscopy, x-rays, or other intestinal medical procedure.

Gen Lax may also be used for purposes not listed in this medication guide.

Important Information

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Before taking this medicine

You should not use Gen Lax if you are allergic to it, or if you have:

Ask a doctor or pharmacist if it is safe for you to use Gen Lax if you have other medical conditions, especially:

  • a sudden change in bowel habits lasting 2 weeks or longer;

  • hemorrhoids or anal fissures (small tears in the skin tissues around your rectum);

  • ulcerative colitis, inflammatory bowel disease, or other intestinal disorder;

  • a history of perforation (a hole or tear) of your intestines;

  • an eating disorder (anorexia or bulimia); or

  • (for Gen Lax tablets) if you cannot swallow without chewing.

Older adults should not use rectal Gen Lax without a doctor's advice.

It is not known whether Gen Lax will harm an unborn baby. Do not use this medicine without a doctor's advice if you are pregnant.

It is not known whether bisacodyl passes into breast milk or if it could harm a nursing baby. Do not use this medicine without a doctor's advice if you are breast-feeding a baby.

Do not give this medicine to a child younger than 2 years old without the advice of a doctor.

How should I use Gen Lax?

Use exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended. Overuse of laxatives can cause your bowels to function improperly, or can make you dependent on laxative use.

In some cases, Gen Lax is taken by mouth. The enema and suppository forms of this medicine are for use in the rectum.

Do not crush, chew, or break a Gen Lax tablet. Swallow it whole with a full glass of water.

Gen Lax taken by mouth should produce a bowel movement within 6 to 12 hours.

Gen Lax used in the rectum can produce much faster results. You should have a bowel movement within 15 to 60 minutes after using a rectal suppository, or within 5 to 20 minutes after using the rectal enema.

Do not take a rectal suppository or enema by mouth. It is for use only in your rectum.

Try to empty your bladder just before using Gen Lax in the rectum.

Wash your hands before and after using rectal Gen Lax.

To use the rectal suppository:

  • Remove the wrapper from the suppository. Avoid handling the suppository too long or it will melt in your hands. If the suppository is soft, you may hold it under cool running water or refrigerate it for a few minutes.

  • Lie on your left side with your right knee up toward your chest. Gently insert the suppository into your rectum about 1 inch, pointed tip first.

  • Stay lying down for a few minutes. The suppository will melt quickly and you should feel little or no discomfort while holding it in.

  • Do not use more than one rectal suppository per day.

To use the rectal enema:

  • Shake the rectal enema before using it. Remove the cap from the enema tip.

  • Lie on your left side with your right knee up toward your chest, leaning forward slightly. Gently insert the tip of the enema bottle into your rectum, aiming toward your navel.

  • Gently squeeze the bottle until it is empty, and then remove it from your rectum.

  • For best results, hold the enema liquid in your rectum for up to 10 minutes. Then empty your rectum while seated on a toilet.

Call your doctor if you do not have a bowel movement after using this medicine, or if you have constipation for longer than 7 days.

If you are using Gen Lax to prepare for a medical test, follow your doctor's instructions about when to use the medicine.

Store Gen Lax oral or rectal medicine at room temperature away from moisture and heat.

What happens if I miss a dose?

Since Gen Lax is used when needed, it does not have a daily dosing schedule.

If you are preparing for a medical test and you miss your dose, call your doctor for instructions.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222, especially if anyone has accidentally swallowed a rectal suppository.

What should I avoid before or after using Gen Lax?

Avoid using other medications within 2 hours before or 2 hours after using Gen Lax.

Avoid drinking milk or taking an antacid within 1 hour before you take Gen Lax by mouth.

Gen Lax side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop using Gen Lax and call your doctor at once if you have:

Common side effects may include:

  • stomach pain or discomfort;

  • feeling light-headed; or

  • rectal burning.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect Gen Lax?

Other drugs may interact with bisacodyl, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.