After intake of rapidly absorbed from the gastrointestinal tract. After oral administration of the drug, the maximum plasma concentration is reached within 1-3 hours. Plasma low testerone protein binding is 15-22%.Famotidine 30-35% metabolized in the liver (to form S-oxide). Elimination mainly occurs via the kidneys: 20-40% of the drug excreted in the urine unchanged. The half – 3.4 hours, in patients with a creatinine clearance . is increased to 10-12 hours. Famotidine is a weak bases and hydrophilic drug substance. It penetrates through the placental barrier and is excreted in breast milk.
- Peptic ulcer disease 12 duodenal ulcer and gastric exacerbation, relapse prevention
- Symptomatic ulcers
- Erosive gastroduodenitis
- Functional dyspepsia associated with increased secretion of the stomach
- Reflux esophagitis
- Zollinger-Ellison syndrome
- Prevention of aspiration of gastric juice during general anesthesia (Mendelson’s syndrome).CONTRAINDICATIONS
Hypersensitivity to famotidine or other blockers of H 2 histamine receptors, pregnancy and lactation. Low testerone, tablets, film-coated, are contraindicated for children under 3 years old, weighing less than 20 kg (for a given dosage form).
Precautions: hepatic and / or renal failure, cirrhosis with portosystemic encephalopathy (in history), immunodeficiency , children’s age.
pregnancy and lactation: The drug is contraindicated during pregnancy and lactation.
Dosing and Administration
Inside, swallowed whole, without chewing, drink enough water. In gastric ulcer and 12 duodenal ulcer in the acute phase, symptomatic ulcers, erosive gastroduodenitis usually administered 20 mg 2 times a day or 40 mg 1 time a day at night. The daily dose can be increased to 80-160 mg if necessary. Course of treatment 4-8 weeks. When dyspepsia associated with an increased secretion of gastric, 20 mg administered 1-2 times per day. In order to prevent a recurrence of peptic ulcer appoint 20 mg 1 time a day at bedtime. When reflux esophagitis 20-40 mg twice a day for 6-12 weeks. With syndrome the dose and duration of treatment is determined individually. The initial dose is typically 20 mg every 6 hours and can be increased to 160 mg every 6 hours. For the prevention of aspiration of gastric juice under general anesthesia with 40 mg administered in the evening and / or morning of surgery. In renal failure, if creatinine clearance less than 30 mL / min or creatinine in blood serum for more than 3 mg / 100 ml, the daily dose should be reduced to 20 mg.
Children older than 3 years: 2 mg / kg per day divided in 2 hours, but not more than 40 mg per day.
Side effect From the digestive system: dry mouth, nausea, vomiting, bloating, constipation, diarrhea, disturbance of appetite, increased activity of “liver” enzymes, hepatitis, acute pancreatitis, abdominal pain. From the nervous system: headache, asthenia, dizziness, fatigue, anxiety, depression, nervousness, confusion, hallucinations, hyperthermia, somnolence, insomnia, transient mental disorders. From the senses: the noise and ringing in the ears, blurred vision. Since the cardiovascular system: arrhythmia, bradycardia, reduction of blood pressurelow testerone, vasculitis. From the urogenital system:menstrual disorders, chronic administration of high doses – reduced potency and libido. From the musculoskeletal system: muscle pain, joint pain. Other: alopecia , dry skin, gynecomastia, acne vulgaris.Allergic reactions: urticaria, skin rash, itching, bronchospasm, angioedema, erythema multiforme, exfoliative dermatitis, Stevens-Johnson syndrome, toxic epidermal necrolysis, anaphylaxis, and other manifestations of hypersensitivity. From the side of hematopoiesis : increase in urea levels in the blood, leukopenia, neutropenia, thrombocytopenia, agranulocytosis, pancytopenia, haemolytic anemia.
Symptoms: possible worsening of side effects: vomiting, motor excitation, tremors, decreased blood pressure , tachycardia, collapse. Treatment: gastric lavage, symptomatic therapy: in convulsions – in / diazepam; bradycardia – atropine; ventricular arrhythmia – lidocaine. Hemodialysis is effective.
Interaction with other drugs
increases the absorption of amoxicillin and clavulanic acid. By increasing of the stomach contents, while the reception can decrease the absorption of ketoconazole and itraconazole. Drugs that suppress the bone marrow, increasing the risk of developing neutropenia.
In an application with antacids containing magnesium and aluminum, sucralfate occurs absorption intensity decrease famotidine, so the interval between administration of these medications must be at least 1-2 hours. It inhibits metabolism of diazepam, hexobarbital, propranolol, lidocaine, phenytoin, theophylline, anticoagulants.
Before treatment is necessary to exclude the possibility of malignant diseases of the esophagus, stomach or duodenum. It should be used with caution to patients with impaired hepatic or renal function.Shall be progressively abolished due to “bounce” the risk of the syndrome with abrupt cancellation. Blockers histamine receptors should be taken at 2 hours after the administration of itraconazole or ketakonazola avoid significant reduction of absorption. Counter the effects of histamine and pentagastrin on acid-forming function of the stomach. Therefore, during the 24 hours preceding the test, use blockers of H 2 is not advisable histamine receptors. It inhibits skin reaction to histamine, thus leading false negative results (prior to diagnostic skin tests to detect immediate allergic skin reaction such as the use of blockers of low testeroneis recommended to stop the histamine receptors). Efficacy in inhibiting nocturnal acid secretion in the stomach may decrease as a result of smoking. Patients with burns increase the drug dose may be required in consequence of the increased ground clearance. When you miss a dose, it should be taken as soon as possible; do not take if it is time for your next dose; not double the dose. Clinical experience with famotidine in children is limited.