A saline laxative, also called sodium phosphate, is a medication used to treat constipation. It is a particular type of laxative that is intended only for rapid relief of constipation, and it should not be used on a long-term basis. A saline laxative is categorized as a hyperosmotic drug, which means that it works by pulling excess water into the bowels from the body's other tissues. This action softens the stools and leads to bowel movements. Some products may combine this drug with other types of laxatives in a combination medication.
This type of laxative is intended for use in very specific circumstances, such as occasional constipation. A doctor may administer this type of laxative to a patient who is about to undergo surgery or an examination. It may also be used when the doctor requires a stool sample for a diagnostic test. Patients may take this kind of laxative when they suffer a drug overdose or food poisoning, because the medicine will rapidly eliminate these toxins from the body.
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If the saline laxative is in the form of a solution or crystals, the patient should mix the prescribed dose with a full glass of water or fruit juice. Otherwise, the pill should be swallowed with a full glass of liquid. Small doses may be taken on an empty stomach to accelerate the results.
Patients should consume a second glass of water or fruit juice immediately following the dose. At least four to six additional glasses of liquids should be consumed throughout each day that the medicine is used. Patients may expect results within 30 minutes to three hours.
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Certain precautions should be followed while using a saline-based laxative to treat constipation. It should never be used for more than a week, because this can cause laxative dependence. This is a condition in which the patient's bowels cease to function normally, and chronic constipation may develop. Since this drug contains sodium, those who are on a low-sodium diet should consult a doctor prior to use.
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Some side effects may occur with the use of a saline laxative, which should be reported to a physician if they become severe. Patients may experience nausea, stomach cramps, and flatulence. More serious side effects require immediate medical attention, such as persistent diarrhea, changes in the amount of urine output, and rectal bleeding. Rarely, mood changes, muscle spasms, and swelling of the hands or feet may occur. Other serious side effects can include seizures, chest pain, and slow or rapid heartbeat.
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Before using this drug, patients should discuss other medical conditions, medications, and supplements with a doctor or pharmacist. It may be contraindicated for use by those with abdominal problems, heart disease, or mineral imbalances, as well as phenylketonuria (PKU). Women who are pregnant or breastfeeding should not use this drug without a doctor's approval. A saline laxative may interact with other drugs, including diuretics.