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Laxatives

Senna

Senna (generic, Senokot®, or Ex-Lax®) tablets are common over-the-counter laxatives that are used to prevent and treat constipation.

 

It works by making the muscles in your gut squeeze more often to move stool through faster. They also draw extra water into the stool to make it easier to pass. At the drug store, these are often called stimulant laxatives.

Which one should I buy?

Drug stores often sell several different brands of senna. The brand does not matter, but we suggest checking the medicine bottle and buying senna that comes in 8.6mg tablets. This tablet strength makes it easiest to increase or decrease your senna based on how your constipation is doing.

How do I take this medicine?

Swallow the pill with a sip of water or another liquid. If you find the pills difficult to swallow, it is safe to crush them and mix them into soft food like applesauce, yogurt or pudding.

Senna is usually taken once or twice per day. Unless your doctor has told you otherwise, it is usually safe to decrease or increase the amount of senna you take up to a maximum dose of four tablets (8.6mg each) twice per day, for a total of 8 tablets per day. This app will give suggestions on how much senna to take based upon your constipation symptoms.

How long does it take to get relief?

Everyone reacts to laxatives differently. This medicine works faster for some people than for others.

Senna often causes a bowel movement in about 6-12 hours after taking it, although it can take longer if you are more severely constipated.

What are the side effects?

The main side effects of senna are belly pain or cramps. Less often, it can cause loose stools, diarrhea, nausea, gas or bloating.

 

Belly cramps from senna are usually the worse when a person is very constipated. This side effect usually goes away after a person has a good-sized bowel movement.

 

If you have severe belly pain, diarrhea or other side effects, talk to your care team. They may suggest a different medication.

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