Ranitidine

Ranitidine is an antiulcer drug, and is included in the category of H2 receptor antagonists.

[1], [2], [3], [4], [5], [6]

Indications Ranitidine

Among the indications:

• aggravated ulcer of duodenum a gut or a stomach;
• preventative against ulcer exacerbation;
• ulcers of symptomatic nature (ulcerous lesions (fast developing) of the stomach or duodenum intestines, which appear under the influence of stresses, reception of various medicinal preparations or pathologies of closely located internal organs);
• erosive form of esophagitis (an inflammatory process in the esophagus, in which the integrity of its mucosa disintegrates), as well as reflux esophagitis (an inflammatory process in the esophagus, provoked by throwing into it the contents of the stomach);
• gastrinoma (a combination of ulcerative lesions of the stomach, and also formed in the prostate benign tumor);
• prevention against the development of violations in the upper gastrointestinal tract, as well as in the period after surgery;
• prevention of possible penetration of gastric juice into the respiratory system in patients undergoing anesthesia surgery.

[7], [8], [9]

Release form

Produced in the form of tablets, as well as injection solution. Tablets have a volume of 0.15, as well as 0.3 g; one packet contains 20, 30 or 100 tablets. The solution is contained in ampoules with a volume of 2 ml.

[10], [11], [12]

Pharmacodynamics

The drug selectively blocks the type H2 receptors of histamine in the lining of gastric mucosa, and also inhibits the secretion of hydrochloric acid. The effect of ranitidine also reduces the total secretory volume, which reduces the concentration of pepsin in the gastric contents.

The antisecretory properties of the drug form the conditions in which ulcerative lesions of the duodenum gut and stomach heal faster. Ranitidine enhances the protective properties of the gastroduodenal tissue: it improves the microcirculation, enhances the restoring effect, and also increases the secretion of mucous elements.

[13], [14], [15], [16],

Pharmacokinetics

After oral administration, it is rapidly absorbed from the digestive tract. The peak concentration is 440-545 ng / ml. His achievement comes 2-3 hours after taking the drug at a dosage of 150 mg. The bioavailability index is approximately 50% (this is due to the effect of the "1st passage" inside the liver). The intake of food does not affect the strength of the substance's absorption.

With plasma proteins binds to 15%. Can penetrate through the histohematological barriers (also through the placenta), but through the BBB is bad. The distribution volume is approximately 1.4 l / kg. Partial biotransformation occurs in the liver. As a result, the main product of the decomposition, N-oxide, is formed, along with the S-oxide, and then their demethylation takes place.

The half-life at a normal creatinine clearance is 2-3 hours. In case of lowering the clearance, this period is extended. The coefficient of kidney cleansing is approximately 410 ml / min (this is an indication of the active process of tubular secretion).

Excretion occurs mainly in the urine - during the subsequent 24 hours after taking (unchanged substance), about 30% (oral intake) or 70% (intravenous administration) of the drug is excreted. Also displayed under the form of N-oxide (less than 4% of the total dose), and in addition S-oxide with desmethylranitidine (1% each).

[17], [18], [19]

Dosing and administration

Dosage is selected individually. For an adult, it is usually 0.15 g twice a day (in the morning and in the evening) or a single dose of 0.3 g at night. The duration of the treatment course is 1-2 months.

As a prophylaxis against exacerbation of ulcers should be consumed at 0.15 g per night. The duration of such a course can be up to 1 year (regular endoscopic control (every four months) is also necessary - examination of the gastric mucosa using a special device used for visual examination).

With gastrinoma, you need to drink 0.15 grams of medication three times a day. If necessary, the daily dosage may be increased to 0.6-0.9 g.

As a prophylaxis against the occurrence of bleeding or ulceration (due to stress) - you need to inject the medicine in / in or / m, at a dosage of 0.05-0.1 g every 6-8 hours.

For children 14-18 years of age, the dosage is 0.15 g twice a day.

Patients suffering from renal insufficiency (the creatinine in the blood serum is more than 3.3 mg / 100 ml), it is necessary to drink the drug twice a day at a dosage of 0.075 g.

[24], [25], [26], [27]

Use Ranitidine during pregnancy

During pregnancy and lactation, the drug should not be taken.

Contraindications

Among the contraindications:

• individual intolerance to the components of the drug;
• children's age is less than 14 years.

Care should be taken when prescribing the medication to patients with impaired renal function.

[20], [21]

Side effects Ranitidine

Among the side reactions:

• organs of the National Assembly: dizziness with headaches, a feeling of fatigue or anxiety, a state of depression, a feeling of sleepiness, as well as vertigo and insomnia. In rare cases, there is a reversible loss of visual acuity, a disorder of eye accommodation, confusion, and the appearance of hallucinations;
• organs of the cardiovascular and hematopoietic systems: AV-blockade, bradycardia or tachycardia, and in addition, arrhythmia, thrombocyto-, leuko- and granulocytopenia. In rare cases, agranulocytosis, aplastic anemia and pancytopenia (in some situations with bone marrow hypoplasia) can develop. Single - IGA;
• organs of the digestive tract: vomiting with nausea, diarrhea or constipation, abdominal pain syndrome. Occasionally, pancreatitis may develop. Single - cholestatic, hepatocellular or mixed form of hepatitis (sometimes it can take place against a background of jaundice) - in this case it is required to immediately cancel the use of the medicine. Such reactions are usually reversible, but occasionally it can reach a lethal outcome. In extremely rare cases, hepatic insufficiency occurred;
• organs ODA: single - pain sensations in the joints or muscles;
• allergies: rashes on the skin, bronchial spasms, eosinophilia or fever. Single - multiform erythema, anaphylaxis and Quincke edema;

Others: occasionally observed vasculitis or hair loss. Single - reduced libido or potency, as well as gynecomastia. Prolonged reception can provoke anemia due to B12 deficiency.

[22], [23]

Overdose

Manifestations of an overdose are convulsions, and in addition, the development of bradycardia and arrhythmia of the ventricles.

As a therapy, it is required to induce vomiting in the patient or to wash his stomach, and then to carry out symptomatic treatment. In case of seizures, diazepam should be administered intravenously; Atropine is administered to eliminate bradycardia, and lidocaine is used to eliminate ventricular arrhythmia.

[28], [29]

Interactions with other drugs

In the case of Ranitidine's combination with antacid drugs, the interval between the use of these drugs (at least 1-2 hours) should be done, since the latter can have a negative effect on the absorption of ranitidine.

[30], [31]

Storage conditions

It is necessary to keep the medicine in standard conditions for medicines - a dark dry place inaccessible to small children. The temperature regime is within 15-30 ° C.

[32], [33], [34]

Shelf life

Ranitidine is allowed to be used within 3 years from the date of manufacture of the drug.

[35]