Magnesia Cinfa 14 Unidosis Envelopes

Magnesia Cinfa (2.4 G 14 Envelopes Oral Suspension 12 Ml)

ACTION AND MECHANISM

- [ANTIACID], [ANTIPEPTIC ULCER]. Magnesium hydroxide is capable of neutralizing gastric hydrochloric acid, giving rise to magnesium chloride and water. It produces an increase in gastric pH, reducing the irritating action of acid and pepsin on the mucosa. Antacid effects depend on the rate of gastric emptying. On an empty stomach they last 20-60 minutes, while with food they last up to 3 hours.

- [LAXANT]. Magnesium hydroxide is also an osmotic laxative, since when it is not absorbed it is capable of increasing the osmotic gradient in the intestine, attracting water to the intestinal lumen. It reduces the consistency of feces and increases its volume, promoting peristalsis. The effects take about 3-6 hours to appear.

PHARMACOKINETICS

Orally:

- Absorption: Magnesium hydroxide is insoluble, so it is not absorbed in the intestine. When reacting with hydrochloric acid, it produces a certain amount of magnesium chloride, which is partially absorbed (15-30%).

Food: Administration of magnesium hydroxide with food determines the time of onset of the effects and their duration. The presence of food delays gastric emptying, increasing the duration of antacid effects and delaying laxative effects. If there is no food, small amounts of gastric juices are released into the duodenum, which reduces the duration of the antacid effects and accelerates the laxatives.

- Elimination: Unabsorbed magnesium is eliminated with feces. The small amount that is absorbed is eliminated through the kidneys, and to a lesser extent with milk and sweat.

Pharmacokinetics in special situations:

- Renal failure: In case of kidney failure, there could be a decrease in the elimination of magnesium, with the consequent risk of hypermagnesemia.

INDICATIONS

- Symptomatic treatment of occasional [CONSTIPATION].

POSOLOGY

- Adults, elderly and adolescents from 12 years of age, oral:

* Envelopes: 1-2 envelopes (2.4-4.8 g)/24 hours.

Administer preferably in the morning, since the laxative effects usually appear after 3-6 hours. Then drink a full glass of water (200 ml).

DOSAGE IN KIDNEY FAILURE

* ClCr > 30 ml/min: Caution, monitoring for possible hypermagnesemia

* CrCl < 30 ml: its use is not recommended due to the risk of hypermagnesemia.

RULES FOR CORRECT ADMINISTRATION

- Suspension: ingest directly, or mixed in water, juices or infusions. It is advisable to take each dose with plenty of liquid (200 ml, a full glass).

ADVICE TO THE PATIENT

- Before starting treatment for constipation, lifestyle habits should be modified. An adequate daily intake of fluids and fiber, responding quickly to the stimulus of defecation, and performing physical exercise are recommended.

- This medication should not be used by patients with intestinal obstructions.

- When used as an antacid, it is recommended to take this medication after meals.

- When used as a laxative, it is recommended to take this medication on an empty stomach before breakfast.

- If after 1 week of use, constipation does not improve, persists or worsens, you should consult your doctor or pharmacist.

- Consult your doctor and/or pharmacist if constipation worsens, or if symptoms such as nausea or vomiting, abdominal bloating or fever appear.

CONTRAINDICATIONS

- Hypersensitivity to any component of the medication.

- Situations that could be aggravated by the laxative effect, such as [INTESTINAL OBSTRUCTION], [INTESTINAL PERFORATION], chronic [INFLAMMATORY BOWEL DISEASE], [APENDICITIS] or [TOXIC MEGACOLON]. Logically, it should not be used in patients with [DIARREA].

- Severe renal failure (CLcr less than 30 ml/minute). The safety and effectiveness of magnesium hydroxide have not been evaluated, so given the possible risk of hypermagnesemia, the use of this medication is not recommended.

PRECAUTIONS

- [RENAL INSUFFICIENCY]. In case of kidney failure, an accumulation of magnesium can occur, with the consequent risk of hypermagnesemia. In patients with mild or moderate renal failure (CLcr between 30-90 ml/minute) a dosage readjustment may be necessary. The efficacy and safety of this medication has not been evaluated in patients with severe renal failure (CLcr less than 30 ml/minute), therefore its use is not recommended.

- Symptoms of intestinal obstruction. Before starting treatment with a laxative, it is advisable to perform a differential diagnosis of intestinal obstruction in patients with symptoms such as [NAUSEA], [VOMITING] or [ABDOMINAL PAIN] of unknown origin, or [ABDOMINAL DISTENSION].

- Long-term treatment. Antacids eliminate the symptoms related to acid diseases, which are common to those of malignant processes such as [STOMACH CANCER] or [ESOPHAGUS CANCER]. Therefore, there is a risk of delaying the diagnosis of these processes.

PRECAUTIONS RELATING TO EXCIPIENTS

- This medicine contains sorbitol. Patients with hereditary [FRUCTOSE INTOLERANCE] should not take this medication.

- This medicine contains sucrose. Patients with hereditary [FRUCTOSE INTOLERANCE], glucose or galactose malabsorption, or sucrase-isomaltase insufficiency should not take this medication.

- This medicine contains sucrose. Its use in oral liquids and pharmaceutical forms that remain in contact with the mouth for a period of time can harm the teeth.

SPECIAL WARNINGS

- Perform a differential diagnosis in patients suspected of intestinal obstruction.

- If the patient experiences symptoms such as dyspepsia, dysphagia, feeling of satiety, symptoms of gastric bleeding, such as melena, hematemesis or anemia, or unexplained weight loss, the existence of esophageal or gastric carcinoma should be ruled out before administering this medication.

- Before starting a treatment, the patient must be properly hydrated and their electrolyte levels must be normal. Treatment should not be started if these levels are altered.

- In elderly or weakened patients, it is recommended to periodically monitor electrolyte levels.

INTERACTIONS

- Emergency contraceptive based on ulipristal acetate. Increased gastric pH may reduce plasma concentrations of the contraceptive, decreasing its effectiveness. Concomitant use is not recommended.

- NSAIDs (mefenamic acid, tolfenamic acid, flurbiprofen, ibuprofen). Clinical cases have been described in which magnesium hydroxide accelerated the absorption of anti-inflammatories. The mechanism of action is unknown.

- Atenolol. Cases have been described in which antacids decreased the absorption of atenolol by up to almost 50%, possibly due to the increase in pH, which would reduce the rate of dissolution of the beta-blocker. Although the interaction has not produced symptoms, it can be important, so it is recommended to distance the administration of both medications by at least 2 hours.

- Atorvastatin. Decreases in atorvastatin serum concentrations of up to 35% have been observed, without affecting the efficacy of atorvastatin. The effect may be due to a decrease in absorption due to an increase in pH or due to the formation of insoluble complexes. It is recommended to distance the administration of both medications by at least 2 hours.

- Bisphosphonates (tiludronic acid). Decreases in tiludronate absorption of up to 60% have been reported when administered with magnesium hydroxide. The effect could be due to the formation of insoluble complexes. Although this interaction has not been proven with other bisphosphonates, it cannot be ruled out. It is recommended to distance the taking of both medications by at least 2 hours.

- Cimetidine. In several studies it has been proven that the administration of cimetidine with antacids can reduce the absorption of the antiulcer agent, although this effect is highly variable, with decreases in bioavailability of 3-48%. The importance of this effect is highly variable, but as a general rule, it is recommended to space the administration of both medications at least 2 hours apart.

- Chlorpromazine. Clinical cases have been described in which the administration of antacids decreased the bioavailability of chlorpromazine by up to 20%, with the consequent risk of loss of its therapeutic effects. The causes of this interaction are unknown, but it could be due to physical adsorption of chlorpromazine by the antacid. It is recommended to distance the administration of both medications by at least 2 hours.

- Digoxin. It has been proven that magnesium hydroxide could decrease the absorption of digoxin, because they can adsorb digoxin on their surface. It is recommended to distance the administration of both medications by at least 2 hours.

- Eltrombopag. Possible reduction in the absorption of eltrombopag due to the formation of insoluble chelates with polyvalent cations. Administer eltrombopag at least 4 hours before or after this medication.

- Erlotinib. Possible reduction in erlotinib levels, due to reduced absorption. Antacids increase gastric pH, which could decrease erlotinib solubility, absorption, and therapeutic effects. It is recommended to administer at least 4 hours before or 2 hours after the daily dose of the antineoplastic agent.

- Phenytoin. There have been some cases of patients in which the administration of antacids could decrease the bioavailability of phenytoin. It is unknown what this effect is due to, but it could be due to changes in the solubility of phenytoin, varying gastric pH, and increased peristalsis. It is recommended to distance the administration of both medications by at least 2 hours.

- Gabapentin. Some decrease in gabapentin levels has been observed when administered together with or within two hours of taking an antacid with magnesium hydroxide and algeldrate. It is recommended that gabapentin be administered 2 hours before an antacid.

- ACEI (captopril, fosinopril). Decreases in bioavailability of 45% for captopril and 30% for fosinopril have been reported in some studies when used with antacids. The mechanism of action is not known. A loss of antihypertensive effects may occur, so it is recommended to space the administration of both medications at least 2 hours apart.

- Ketoconazole. It has been proven that antacids could decrease the absorption of ketoconazole, with the possible loss of therapeutic efficacy. It is recommended to distance the administration of both medications by at least 2 hours.

- Lansoprazole. A reduction in the area under the curve of 13% and Cmax of 27% has been proven in pharmacokinetic studies. The effects seem to be due to a lower absorption of lansoprazole due to the increase in pH. It is recommended to separate the administration of these medications by at least 1 hour.

- Penicillamine. It has been proven that antacids could decrease the absorption of penicillamine by around 35%, probably due to the formation of insoluble complexes. Due to the possible loss of therapeutic effect, it is recommended to distance the administration of both medications by at least 2 hours.

- Sodium polystyrene sulfonate. There have been cases of patients treated with magnesium hydroxide and polystyrene in whom metabolic alkalosis occurred. The effect could be due to the union of polystyrene and magnesium, which would prevent magnesium from neutralizing bicarbonate ions, which would enter the blood, giving rise to alkalosis. It is recommended to avoid this association, especially in metabolically unstable patients.

- Prednisone. Significant reductions (25-50%) in the bioavailability of prednisone have been observed when administered with antacids. The mechanism of action is unknown, but it is recommended to distance the intake of both medications by at least 2 hours or to replace prednisone with prednisolone.

- Quinidine. There have been clinical cases of patients with decreased renal clearance and quinidine toxicity when administered in combination with antacids. The effect could be due to an alkalinization of the urine. It is recommended to avoid the association, and if necessary, monitor the dosage of quinidine.

- Quinolones (ciprofloxacin, enoxacin, sparfloxacin, moxifloxacin, norfloxacin, ofloxacin, perfloxacin). Many cases have been described of significant reductions in the bioavailability of quinolones when administered with antacids, which could even lead to therapeutic failure of the antibiotic. The effects could be due to the formation of insoluble complexes when metal cations bind to the quinolone nucleus. It is recommended to distance the administration of both medications by at least 2 hours.

- Ranitidine. It has been proven in studies that antacids could decrease plasma levels by around 30%, apparently due to a decrease in the absorption of ranitidine due to changes in pH. It is recommended to avoid this association or use at least low doses of antacids.

- Iron salts. Cases have been described in which magnesium hydroxide and other antacids decreased the absorption of iron salts. The effects could be due to the formation of poorly soluble complexes. It is recommended to distance the intake of these iron supplements and magnesium antacids by at least 2 hours.

- Salicylates (acetylsalicylic acid, salicylic acid). There have been cases of patients being treated with magnesium hydroxide and salicylates, in which a decrease in plasma levels of salicylate occurred, probably due to alkalinization of the urine. There could be a loss of effectiveness of salicylates.

- Sulpiride. Pharmacokinetic studies have shown that antacids could reduce the bioavailability of sulpiride by up to 32%. It is recommended to distance the taking of both medications by at least 2 hours.

- Tetracyclines (chlortetracycline, demeclocycline, doxycycline, tetracycline). There have been many cases in which the administration of antacids decreased the bioavailability of tetracyclines, because they form insoluble complexes with di- and trivalent cations. There is a risk of loss of efficacy, so the administration of both medications must be separated by at least 2 hours.

- Vitamin D. Magnesium competes with calcium in its absorption, both being facilitated by vitamin D. Patients treated with vitamin D and magnesium antacids could develop hypermagnesemia, especially in patients with kidney failure. It is recommended to avoid this association.

PREGNANCY

Safety in animals: no data available.

Safety in humans: administer with caution due to the risk of hypermagnesemia.

Effects on fertility: no specific studies have been performed in humans.

LACTATION

Safety in animals: no data available.

Safety in humans: magnesium is excreted in small amounts in breast milk, but no alterations have been observed

in infants. It can be used, although it is recommended to avoid excessive doses or prolonged consumption.

CHILDREN

Magnesium is excreted in small quantities with milk, so there have been cases of diarrhea in infants. However, no serious effects are expected, so it can be used, as long as it is not used in high doses or for prolonged periods of time.

ADVANCED AGE

There is no recommendation for use in these patients.

ADVERSE REACTIONS

The adverse effects of magnesium hydroxide are generally mild and transient. The most characteristic adverse reactions are:

- Digestive. The appearance of [DIARREA] is common (1-9%).

- Hydroelectrolytic. In specific cases, especially in prolonged treatments or in patients with significant renal failure, [HYPERMAGNESEMIA] could occur (See Overdose).

ADVERSE REACTIONS RELATING TO EXCIPIENTS

- Because it contains propyl parahydroxybenzoate, it may cause [ALLERGY TO PARABENS], possibly delayed.

- Because it contains methyl parahydroxybenzoate, it may cause [ALLERGY TO PARABENS], possibly delayed.

OVERDOSE

Symptoms: After an overdose, diarrhea is expected. If the overdose is severe, hypermagnesemia may occur. Symptoms of hypermagnesemia include flushing, thirst, hypotension, nausea, vomiting, asthenia, confusion, dizziness, blurred vision, ataxia, and muscle weakness. In the most serious cases, cardiac arrhythmias, respiratory depression, coma and even death due to cardiac arrest may occur.

Treatment: Administration of the medication should be stopped immediately. The elimination of magnesium from the body should be accelerated through peritoneal dialysis and administration of calcium chloride. A forced diuresis may also be performed by administering diuretics such as furosemide or ethacrynic acid. In the event that hydroelectrolyte imbalances appear, electrolyte solutions may be administered.

Magnesia Cinfa Leaflet 14 Unidosis Envelopes