Mild Laxatives: Understanding Their Gentle Relief Mechanism

Laxatives are a type of medicine used to treat constipation. They are available over the counter without a prescription and can be bought from pharmacies and supermarkets. There are four main types of laxatives: bulk-forming laxatives, osmotic laxatives, stimulant laxatives, and stool softener laxatives. They work by softening hard stools or stimulating the bowels to get moving. They are generally considered safe and effective, but it is important to use them sparingly and follow the instructions on the medication to prevent side effects such as bloating, gas, and stomach cramps.

Bulk-forming laxatives

Some common bulk-forming laxatives include:

• Psyllium (Metamucil)
• Inulin (Metamucil Simply Clear)
• Wheat dextrin (Benefibre)
• Methylcellulose (Citrucel)
• Polycarbophil (FiberCon, Prodiem)
• Fybogel (ispaghula husk)

Osmotic laxatives

• Polyethylene glycol (PEG): An organic compound derived from petroleum that can be safely ingested to manage constipation. Available over the counter, PEG-containing laxatives include Miralax and GlycoLax.
• Lactulose: A type of sugar that is not absorbed by the intestine. It sits and ferments in the intestines, producing fatty acids that draw water into the lumen. Available by prescription, lactulose-containing laxatives include Cephulac, Duphalac, and Kristalose.
• Sorbitol: Another non-absorbable sugar with an action similar to lactulose. Over-the-counter (OTC) and prescription versions are available, including Arlex and GeriCare.
• Magnesium citrate: Magnesium in salt form combined with citric acid. The salts help draw water into the lumen. OTC versions include Citrate of Magnesia, Citroma, and LiquiPrep.
• Magnesium hydroxide: A milder form of magnesium sold under the brand name Milk of Magnesia. Available over the counter, Milk of Magnesia is also used as an antacid.

As with all medications, osmotic laxatives can cause side effects, although most are relatively mild and will resolve within a couple of days. Common side effects include nausea, bloating, cramping, flatulence, and diarrhoea. Overuse of osmotic laxatives can lead to dehydration and the loss of electrolytes like sodium, calcium, and potassium, which are essential for regulating heartbeats, muscle contractions, and other key functions. Therefore, it is important to follow dosing instructions carefully and only use laxatives when needed.

Stimulant laxatives

Laxatives are a type of medicine used to treat constipation. They are often used when lifestyle changes, such as increasing fibre intake, drinking more fluids, and exercising, have not helped.

There are four main types of laxatives: bulk-forming, osmotic, stool softeners, and stimulants. This answer will focus on stimulant laxatives.

It is important to note that stimulant laxatives should not be used for more than a week unless advised by a doctor. They can be habit-forming and may cause harm to the bowels if used long-term. They are not recommended for children under six without a paediatrician's instruction.

Before using stimulant laxatives, it is crucial to consult a doctor, especially if you have any current health conditions or are pregnant or breastfeeding.

Stool softener laxatives

Stool softeners are a type of laxative called an emollient laxative. This means that all stool softeners are a type of laxative, but not all laxatives are stool softeners. Stool softeners are gentle medications with a relatively mild effect, making them ideal for people with temporary, mild, or chronic constipation. They are also often prescribed after major surgeries, such as heart surgery or hernia repair, to avoid complications that may arise from straining during bowel movements.

Stool softeners work by gently lubricating the stool and adding a compound to it that absorbs water, helping to wet and soften the stool, making it easier to pass. The active ingredients in stool softeners are typically docusate sodium and docusate calcium. Although it might take a week or longer for emollient laxatives to be effective, they are a good option for preventing constipation with regular use.

It is important to note that, while generally safe, oral stool softeners may cause throat irritation when swallowed. As with all laxatives, it is recommended to consult a healthcare professional before taking them, as they may interact with other medications, vitamins, or supplements.

Lubricant laxatives

This type of laxative is highly effective in providing short-term relief from constipation. However, it is recommended that they are not used for extended periods. This is because mineral oil can interfere with the absorption of certain vitamins and medications. Lubricant laxatives can reduce the absorption of fat-soluble vitamins such as vitamins A, D, E, and K. They can also decrease the absorption of specific prescription drugs, leading to reduced effectiveness. Therefore, it is advised not to take mineral oil concurrently with other medications or supplements.

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