Usage
Magnesium citrate is primarily used as a saline laxative to treat occasional constipation. It is also used for bowel preparation before medical procedures such as colonoscopies. It can also be used as a magnesium supplement for treating magnesium deficiency. It falls under the pharmacological classifications of laxative and mineral supplement. It works by increasing the osmotic pressure in the intestinal lumen, drawing water into the intestines, softening the stool, and stimulating bowel movements.
Alternate Names
Magnesium citrate is also known as Citrate of Magnesia, Citroma, and LiquiPrep.
How It Works
Pharmacodynamics: Magnesium citrate acts as an osmotic laxative. It increases the osmotic pressure within the intestinal lumen, drawing water into the bowels. This increased water content softens the stool and stimulates peristalsis, resulting in bowel evacuation.
Pharmacokinetics:
- Absorption: Orally administered magnesium citrate is poorly absorbed in the gastrointestinal tract. The unabsorbed portion exerts its osmotic laxative effect. A small portion of magnesium is absorbed systemically.
- Metabolism: Absorbed magnesium is not metabolized.
- Elimination: Unabsorbed magnesium citrate is excreted in the feces. Absorbed magnesium is primarily excreted by the kidneys. Renal excretion is influenced by magnesium status, parathyroid hormone, and serum calcium levels.
Dosage
Standard Dosage
Adults:
For constipation, the standard dose is 195-300 mL of the oral solution once daily, or 2-4 tablets at bedtime. For nutritional supplementation, the recommended daily allowance varies based on age and sex, typically ranging from 310-420 mg per day for adults.
Children:
- 2-6 years: 60-90 mL of the oral solution once daily or in divided doses, not to exceed 90 mL in 24 hours.
- 6-12 years: 90-120 mL of the oral solution once daily or in divided doses.
- Over 12 years: Adult dosage.
- Under 2 years: Safety and efficacy not established.
Special Cases:
- Elderly Patients: Start with a lower dose and adjust as needed based on tolerance and response. Consider renal function.
- Patients with Renal Impairment: Use with caution due to risk of hypermagnesemia. Dose adjustment or avoidance might be necessary depending on the degree of impairment.
- Patients with Hepatic Dysfunction: No specific dose adjustment is typically needed.
- Patients with Comorbid Conditions: Individualized dosing may be required based on specific conditions.
Clinical Use Cases
Dosages for specific clinical use cases, such as intubation, surgical procedures, mechanical ventilation, ICU use, or emergency situations, are not standardized for magnesium citrate and are usually tailored according to the specific needs of each patient by a healthcare professional. Instead, other forms of magnesium, such as magnesium sulfate, are typically preferred in these settings.
Dosage Adjustments
Dose adjustments may be required in patients with renal impairment. In severe renal insufficiency, magnesium citrate should be avoided.
Side Effects
Common Side Effects:
- Abdominal cramping
- Diarrhea
- Nausea
- Vomiting
- Flatulence
Rare but Serious Side Effects:
- Allergic reactions (skin rash, itching, hives, facial swelling)
- Hypermagnesemia (confusion, drowsiness, flushing, muscle weakness, irregular heartbeat, breathing difficulties)
- Electrolyte imbalances (especially in patients with underlying conditions)
- Severe dehydration
Long-Term Effects:
Chronic use of high doses may lead to dependence or electrolyte imbalances.
Adverse Drug Reactions (ADR):
Clinically significant ADRs include severe hypermagnesemia and allergic reactions, requiring immediate medical intervention.
Contraindications
- Known hypersensitivity to magnesium citrate
- Bowel obstruction
- Renal failure
- Untreated dehydration
- Myocardial damage or heart block
- Rectal bleeding
- Fecal impaction
- Appendicitis
Drug Interactions
Magnesium citrate can decrease the absorption of certain medications, such as some antibiotics (tetracyclines, quinolones), bisphosphonates, and levothyroxine. It can also interact with other medications that affect magnesium levels, such as diuretics and certain heart medications. It is important to inform your physician about all the medications you are taking, including over-the-counter drugs and supplements.
Pregnancy and Breastfeeding
Magnesium citrate is generally considered safe during pregnancy and breastfeeding when used at recommended doses. However, some research suggests that it may delay the onset of lactation. Consult a healthcare professional before use, especially during pregnancy.
Drug Profile Summary
- Mechanism of Action: Osmotic laxative; increases intraluminal pressure and stimulates peristalsis.
- Side Effects: Abdominal cramping, diarrhea, nausea, vomiting, flatulence. Serious side effects are rare but can include hypermagnesemia and allergic reactions.
- Contraindications: Hypersensitivity, bowel obstruction, renal failure, dehydration, heart block, myocardial damage, appendicitis, rectal bleeding, fecal impaction.
- Drug Interactions: Can decrease absorption of some antibiotics, bisphosphonates, levothyroxine. Consult with a healthcare professional regarding concomitant medications.
- Pregnancy & Breastfeeding: Generally considered safe; may delay lactation onset. Consult a healthcare professional before use.
- Dosage: Constipation: Adults: 195-300 mL oral solution or 2-4 tablets daily. Nutritional supplementation: Varies by age and gender; generally 310-420 mg/day for adults. Pediatric dosages are available for different age groups.
- Monitoring Parameters: Serum magnesium levels, electrolyte levels, bowel movements.
Popular Combinations
Magnesium citrate is not typically used in combination with other drugs for specific therapeutic benefits.
Precautions
Consult a healthcare professional before using magnesium citrate if you have kidney disease, stomach pain, nausea, vomiting, sudden changes in bowel habits, or are pregnant or breastfeeding. Avoid prolonged or excessive use without medical supervision.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Magnesium Citrate?
A: For constipation: Adults: 195-300 mL oral solution or 2-4 tablets daily. For nutritional supplementation: 310-420 mg/day for adults. Pediatric dosages are available.
Q2: How long does it take for Magnesium Citrate to work?
A: It can take from 30 minutes to 6 hours to produce a bowel movement.
Q3: Can I take Magnesium Citrate every day?
A: Magnesium citrate is intended for occasional use for constipation. Consult with a doctor for daily or long-term use.
Q4: What are the serious side effects of Magnesium Citrate?
A: Serious side effects are rare but can include allergic reactions, hypermagnesemia (high magnesium levels), severe dehydration, and electrolyte imbalances.
Q5: Who should not take Magnesium Citrate?
A: Individuals with bowel obstruction, renal failure, untreated dehydration, certain heart conditions, rectal bleeding, fecal impaction, or appendicitis should not take magnesium citrate.
Q6: Can I take Magnesium Citrate if I am pregnant or breastfeeding?
A: Consult a healthcare professional before using magnesium citrate during pregnancy or breastfeeding. It is generally considered safe at recommended doses, but some studies suggest it may delay the onset of lactation.
Q7: What should I do if I miss a dose of Magnesium Citrate?
A: If you miss a dose for constipation relief, take it as soon as you remember. If it is close to your next scheduled dose, skip the missed dose. If you are taking it for supplementation, take the missed dose as soon as possible, but skip it if it is close to your next dose. Do not double the dose to catch up.
Q8: How should Magnesium Citrate be stored?
A: Store at room temperature or in the refrigerator according to package instructions. Discard opened bottles of the oral solution after 24 hours.
Q9: Can I mix Magnesium Citrate with other medications?
A: Magnesium citrate can interact with certain medications. Consult your doctor or pharmacist before mixing it with other medications to avoid potential drug interactions.
Q10: What if I experience side effects after taking Magnesium Citrate?
A: If you experience mild side effects, such as abdominal cramping or diarrhea, discontinue use and consult your doctor or pharmacist. If you experience severe side effects, such as allergic reactions or signs of hypermagnesemia, seek immediate medical attention.
