Alendra

Alendra is a drug that affects bone mineralization and structure.

Alendronate Na is a representative of the aminobisphosphonate category, an artificial analogue of natural pyrophosphate. The drug suppresses the precipitation processes of Ca phosphate, blocks the process of its conversion into hydroxyapatite, and in addition, slows down the aggregation of apatite crystals, forming larger crystals, and increases the rate of reverse dissolution of these crystals. [ 1 ]

The selective effect is related to the strong affinity observed in bisphosphonates for mineral bone elements. The drug acts as an effective (non-hormonal) specific substance that slows down osteoclast-mediated bone resorption. The exact principle of development of this process has not yet been fully determined.

Indications Alendra

It is used to treat osteoporosis that develops during postmenopause. The drug reduces the likelihood of fractures in the hip bone area, as well as the spine. [ 2 ]

Release form

The release of the therapeutic substance is realized in tablets - 4 pieces inside a blister pack. In a box - 1 such pack.

Pharmacodynamics

The drug helps to establish a positive balance in relation to bone restoration and resorption. Increases the mineral bone density in the pelvic area with the spine and helps to form bone tissues with a healthy histological structure. [ 3 ], [ 4 ], [ 5 ]

Alendra prevents the occurrence of new bone fractures. Reduces serum Ca values, slowing bone resorption and reducing its volumes released from bone tissue.

The calcium-lowering effect of the drug, mediated through the inhibition of osteoclasts, develops after 1-2 days.

Pharmacokinetics

Alendronate Na is 25% absorbed in the gastrointestinal tract. The absolute bioavailability of tablets (within 5-10 mg), taken on an empty stomach 2 hours before meals, is 0.64% (in women) and 0.59% (in men). [ 6 ], [ 7 ], [ 8 ]

The bioavailability index decreases (by approximately 40%) if the drug is taken 0.5-1 hour before a regular breakfast. The bioavailability values of the drug will be low if it is taken with food or within 2 hours after eating. Taking the drug with any drinks (including coffee, mineral water and orange juice) reduces its bioavailability values by 60%.

Animal studies have shown that after intravenous injection of 1 mg/kg alendronate Na, the substance is temporarily distributed within soft tissues but then redistributes fairly rapidly.

Half of the portion that was absorbed is excreted unchanged mostly through the kidneys (over a period of 72 hours), the remainder accumulates in bone tissue for a long time. Its excretion occurs extremely slowly - due to synthesis with bone tissue. The half-life of the drug from bones lasts for several years.

About 78% of the substance is synthesized with intraplasmic protein and does not participate in metabolic processes. Plasma values of the drug are quite low (below 5 ng/ml) and decrease by 95% in the period of 6 hours after the infusion. [ 9 ]

With a single use of 10 mg of the drug, the intrarenal clearance rates were equal to 71 ml per minute; the total clearance was a maximum of 0.2 l per minute. [ 10 ], [ 11 ], [ 12 ], [ 13 ]

Dosing and administration

The medication should be used in a dose of 70 mg (1 tablet), 1 time per week.

There is no optimal duration of a course of bisphosphonate therapy for osteoporosis. The decision regarding the need to continue the course should be made by the treating physician, individually for each patient, taking into account the benefit-risk ratio (especially after 5+ years of taking the medication).

The tablet is swallowed with plain water, at least half an hour before the first meal, drink or other medication. Other drinks (including mineral water), food and certain medications can reduce the absorption of alendronate Na.

To facilitate the passage of the medicine into the stomach, which will reduce its irritating effect on the mucous membranes of the oropharynx and esophagus, you need to take the medicine with at least 0.2 liters of plain water (in the morning, after sleep); you cannot chew the tablet, because this can provoke the appearance of ulcers in the oropharynx. The first meal of the day should occur at least half an hour after taking the first tablet. The patient should not lie down for at least half an hour after the administration of the drug. It is forbidden to take the medicine in the evening before going to bed or when getting out of bed in the morning.

There should be at least a half hour gap between taking Alendra and other medications (taken orally).

Additional intake of calciferol with Ca is required in cases where insufficient amounts of these elements are supplied with food. [ 19 ], [ 20 ]

The medication must be taken on the same day of the week. If a dose is accidentally missed, the tablet is taken in the morning the next day. Then the use continues according to the usual scheme - a new tablet is taken on the day originally chosen for use.

Use Alendra during pregnancy

Alendra should not be administered to pregnant or breastfeeding women.

Contraindications

Among the contraindications:

• severe intolerance associated with alendronate Na or another element of the drug;
• hypocalcemia;
• diseases affecting the esophagus (achalasia or stricture), in which there is a delay in the removal of its contents;
• inability to stand or sit upright for at least half an hour;
• severe renal failure (creatinine clearance values <35 ml per minute). [ 14 ], [ 15 ], [ 16 ]

Side effects Alendra

Main side effects:

• immune damage: signs of intolerance, including manifestations of allergies, urticaria and Quincke's edema;
• disorders associated with the function of the nervous system: dizziness or headaches, as well as taste disorders (the appearance of an unusual or bitter taste after taking a drug);
• visual disturbances: episcleritis or scleritis, as well as uveitis;
• problems with the functioning of the hearing organs: osteonecrosis affecting the outer part of the ear canal (a complication often encountered with the use of bisphosphonates) and vertigo;
• signs related to the gastrointestinal tract: constipation, ulcers in the mouth, esophagus or pharynx, heartburn, abdominal pain, bloating, dysphagia and dyspepsia, as well as vomiting, erosion in the esophagus, tension of the abdominal wall, nausea, esophagitis and regurgitation of the stomach contents. In addition, strictures inside the esophagus, melena and perforations, bleeding or ulcers in the gastrointestinal tract (oral cavity, stomach with esophagus and pharynx) may appear;
• lesions of the subcutaneous layers and epidermis: erythema, alopecia, rashes, photosensitivity, itching and epidermal manifestations, including TEN and SJS;
• problems with the functioning of connective tissues and the musculoskeletal system: osteonecrosis of the jaw, pain affecting joints with bones or muscles, swelling in the joint area and atypical fractures in the femur area;
• metabolic disorders: hypocalcemia, which is accompanied by corresponding clinical signs (usually associated with the presence of provoking factors);
• systemic manifestations: temporary disturbances (malaise and muscle pain; occasionally – fever), often developing at the initial stage of therapy, and in addition peripheral edema and asthenia;
• laboratory test results: hypocalcemia or -phosphatemia (in case of using 10 mg/kg alendronate per day). [ 17 ], [ 18 ]

Overdose

In case of poisoning, hypophosphatemia and -calcemia develop, as well as negative manifestations affecting the upper gastrointestinal tract (heartburn, gastric dysfunction, gastritis, esophagitis or gastric ulcer).

To synthesize alendronate, it is necessary to drink milk or use antacids. Due to the existing possibility of irritation in the esophagus, vomiting should not be induced; in addition, the victim must remain in an upright position at all times.

Interactions with other drugs

Impaired absorption of the drug may occur when taken with drinks (including mineral water), food, antacids, Ca substances (including food additives) and certain other drugs for oral administration. The interval between the use of such substances should be at least half an hour.

The administration of NSAIDs may have an irritating effect on the gastrointestinal mucosa. Therefore, it is necessary to combine such medications with Alendra very carefully. [ 21 ], [ 22 ], [ 23 ], [ 24 ], [ 25 ]

Storage conditions

Alendra should be stored in a place closed to small children. Temperature values should not exceed 25°C. [ 26 ]

Shelf life

Alendra can be used for a period of 3 years from the date of manufacture of the pharmaceutical product.

Application for children

The medication is not used in pediatrics (under 18 years of age).

Analogues

Analogues of the drug are Londromax and Ostemax. [ 27 ], [ 28 ], [ 29 ]