How Long Does It Take For A Laxative To Work?

Constipation is an uncomfortable but very common condition in which you have fewer bowel movements than normal and stool becomes hard and difficult to pass. While most people experience constipation from time to time, some may need help in finding relief.

Laxatives are medications that can help ease the symptoms of constipation, but how long does it take for a laxative to work?

What are laxatives?

Laxatives are a type of medication that is commonly used to treat symptoms of constipation by encouraging your digestive tract to have a bowel movement.

Constipation is a common issue that affects many people occasionally, and there are many different types of laxatives available to help treat the condition.

Each type of laxative works a bit differently and some may work more quickly or slowly than others and continue working for different periods of time. How long it takes for a laxative to work depends on which type of laxative you take to treat your constipation.

What is constipation?

Constipation is a common medical condition that occurs when people have difficulty having a bowel movement and do not have bowel movements as often as they normally do. Different people have bowel movements at different frequencies, so constipation is defined by what is normal for each individual.

For example, some people have multiple bowel movements a day, while others may have bowel movements every other day or less. When people experience constipation, their stools become hard and difficult or painful to pass.

Constipation can cause bloating, pain, and cramps in the abdomen. There are two main types of constipation, including primary constipation and secondary constipation. Primary constipation occurs when bowel movements decrease as a result of an anatomical issue that causes intestinal movements to slow down. The most common causes of primary constipation include not getting enough fiber as part of your daily diet or not drinking enough fluids throughout the day. Secondary constipation occurs when metabolic diseases, such as diabetes, neurologic diseases, such as Parkinson’s disease, connective tissue disorder, or eating disorders impact the way that the digestive tract works.

Constipation can also occur when patients are taking certain types of medications, including iron supplements, opioids, calcium channel blockers, sympathomimetics, antidepressants, anticholinergics, antacids, nonsteroidal anti-inflammatory drugs (NSAIDs), and antipsychotics. Constipation can occur regardless of whether the medication is purchased over the counter or by prescription.

How long does it take for a laxative to work?

Each type of laxative works differently to treat constipation, so they also start working at varying speeds. An explanation of the different types of laxatives is presented in the following section.

• Stimulant laxatives: 6 to 12 hours
• Emollient laxatives: 12 to 72 hours
• Lubricant laxatives: 6 to 8 hours
• Bulk-forming laxatives: 12 to 24 hours for partial relief, 48 to 72 hours for full relief
• Suppository laxatives: 15 to 30 minutes
• Hyperosmotic laxatives: 6 to 8 hours

Each type of laxative takes a different amount of time to work and they also stay in the body for different lengths of time. The amount of the laxative taken, the active ingredient used, and the way the medication is absorbed all affect how long a laxative stays in your system.

What are the different types of laxatives and how do they work?

There are six main types of laxatives, each of which works differently to treat constipation. The six types of laxatives include stimulant laxatives, emollient laxatives, lubricant laxatives, bulk-forming laxatives, suppository laxatives, and hyperosmotic laxatives.

Stimulant laxatives

The active ingredient in stimulant laxatives causes the muscles of the bowels to contract, helping stubborn stool to pass more quickly. There are several different active ingredients that can be used in stimulant laxatives, including senna, bisacodyl, and sodium picosulphate. Compared to most other types of laxatives, stimulant laxatives work quickly to provide relief from constipation symptoms; generally, stimulant laxatives take about 6 to 12 hours to start working.

Emollient

Commonly referred to as stool softeners, emollient laxatives are a popular type of laxative that work by drawing water into the stool, making it softer and easier to pass. Emollient laxatives typically take between 12 and 72 hours to start working, so they may not be the best option for severe constipation. The active ingredient most commonly used in emollient laxatives is docusate.

Lubricant laxatives

Lubricant laxatives typically do not contain medication and are made up of different types of oil, such as mineral oil. When using a lubricant laxative, the laxative covers the stool in a slippery waterproof film. The film serves to seal moisture into the stool and allows the stool to travel more easily through the bowel, making passage easier. When using a lubricant laxative, you can expect the laxative to start working in about six to eight hours.

Bulk-forming laxatives

Bulk-forming laxatives work the same way to treat constipation as fiber from the foods that we eat. Fiber and bulk-forming laxatives both work by helping to draw water into the bowels and stool, which causes the stool to become larger and softer. Stools without sufficient moisture content become small, hard, and difficult to pass, so adding bulk to these stools helps make bowel movements easier.

This type of laxative commonly includes active ingredients like psyllium, methylcellulose, and sterculia. Bulk-forming laxatives work more slowly than some other types of laxatives, which is why it is so important to eat enough fiber every day. Most people will notice some effects of bulk-forming laxatives after 12 to 24 hours, while receiving full effect may take 48 to 72 hours.

Suppositories

Suppository laxatives work the most quickly out of all types of laxatives, typically taking effect within as little as 15 to 30 minutes. Unlike other laxatives, which are ingested orally, suppositories are inserted into the recturm, allowing the medication to quickly dissolve and enter the bloodstream and muscles of the bowels.

Active ingredients included in suppository laxatives include bisacodyl and glycerol. Suppository laxatives typically work to treat constipation in one of two ways, including stimulating the muscles of the bowels to help you pass stool or softening the stool to make it easier to pass.

Hyperosmotic laxatives

Hyperosmotic laxatives work by increasing the amount of fluid that is in the bowels, which helps to soften up the stool and make it easier to pass through the bowel.

Hyperosmotic laxatives can be made from active ingredients that include:

• Lactulose
• Saline
• Polymer

Lactulose hyperosmotic laxatives use a sugar-like compound called lactulose as the active ingredient and typically start working in 48 to 72 hours. This type of laxative is best suited for use in patients who suffer from long-term or chronic constipation, perhaps due to a medical condition or use of a certain medication.

Saline hyperosmotic laxatives use a salt water solution to treat constipation. This type of laxative works quickly, typically in just 30 minutes to 3 hours, and is best suited for the short term treatment of occasional constipation.

Polymer hyperosmotic laxatives use active ingredients like polyethylene glycol, which is made up of large molecules that help draw liquid into the stool. Best suited to the short term treatment of acute constipation, polymer hyperosmotic laxatives typically take six or more hours before they start working.

Are there any risks associated with laxative use?

Many laxatives are available over the counter, but that doesn’t mean that they are without risk. It’s important to follow all of the instructions on your laxative’s label in order to minimize your risk of side effects.

Risks associated with laxative use include:

• Decreased bowel motility
• Dehydration and/or electrolyte imbalance
• Pregnancy and breastfeeding considerations
• Interactions with other medications

Decrease in bowel motility:

Occasional constipation is something that most people will experience over the course of their lifetime, but if you regularly struggle with constipation and use laxatives too often, you could experience dysfunction in the natural movement of your bowels. Laxatives should always be used as directed and in moderation only in order to avoid damaging your bowel function. Make sure to talk to a doctor if you regularly struggle with constipation.

Dehydration or electrolyte imbalance:

Many types of laxatives work to soften stool by bringing water into the bowels from other parts of the body. If you don’t drink enough water while using laxatives, you could experience dehydration or electrolyte imbalance. Drinking enough water is also key in preventing constipation from occurring in the first place, so make sure you are drinking enough throughout the day.

Pregnancy and breastfeeding considerations:

Pregnant women should speak to their doctors before using laxatives. Constipation commonly occurs during pregnancy as the growing fetus presses on the bowels, but not all types of laxatives are safe for use in pregnant women. Talk to your doctor before using one. While laxatives are generally safe for women who are breastfeeding, some ingredients can pass through breast milk to a nursing baby, potentially causing diarrhea. If you’re breastfeeding, talk to your doctor before using laxatives.

Interactions with other medications:

Depending on the type of laxative that you choose, your laxative could interact with other over the counter and prescription medications that you may be taking. Antibiotics and heart medications in particular are known to interact with laxatives. If you have questions, talk to your doctor or pharmacist.

Summary

The length of time that it takes for a laxative to work depends on the type of laxative that you take. Some laxatives may start working in as little as 15 minutes, while other laxatives can take up to 72 hours to take full effect. There are six main categories of laxatives on the market, so if you are unsure what’s best for you, talk to your doctor about the pros and cons of each type.