Bisphosphonates are drugs that block the breakdown of bone tissue. For this reason, they are used in the treatment of many diseases of the skeletal system. They are one of the most important groups of drugs used in the treatment of osteoporosis. They are highly effective in treating this disease. The action of these substances, like all drugs, is associated with certain side effects. What should I know when taking bisphosphates?

Bisphosphonatesare a class of drugs that have been shown to work to prevent bone loss. They are used to treat osteoporosis. and diseases in the course of which mineral substances are degraded in bone tissues. These are the most commonly prescribed drugs for the treatment of osteoporosis.

Contents:

  1. Bisphosphonates - action
  2. Bisphosphonates - story
  3. Bisphosphonates - used in the treatment of osteoporosis
  4. Bisphosphonates - start of therapy
  5. Bisphosphonates in injections and tablets
  6. Bisphosphonates - it's worth knowing
  7. Bisphosphonates - side effects

Scientific evidence shows that these drugs reduce the risk of bone fractures in postmenopausal women with osteoporosis by up to 70%. Their proven effectiveness makes bisphosphonates so often recommended by specialists as the main drug therapy for this disease.

Medical situations in which bisphosphonates are used:

  • prevention and treatment of osteoporosis
  • Paget's disease
  • tumor metastases to the bone
  • multiple myeloma
  • primary hyperparathyroidism
  • osteogenesis disorders
  • fibrous dysplasia
  • other bone fragility conditions

Bisphosphonates - action

In order to understand the mechanism of action of bisphosphonates, it is necessary to understand the processes taking place in the bone tissue. We often imagine bones as a kind of dead inner rack. However, this is a wrong picture. Our skeleton, at the cellular level, is extremely dynamic.

Bone tissue is undergoing constant reconstruction. Its homeostasis, or equilibrium, is maintained by specialized cells. Among them, we distinguish osteoblasts, which are designed to create bone and destroy itosteoclasts. Both processes take place simultaneously in the tissue.

Bisphosphonates by their activity inhibit the processes that break down bones. This is because they encourage osteoclasts to apoptosis, or kill themselves. Due to the fact that these cells, sometimes called osteophytes, are responsible for the destruction of bone tissue, their killing prevents its loss.

Bisphosphonates are fairly simple chemicals. It may seem puzzling that such primitive particles recognize osteoclasts and initiate their death. However, this can be explained quite simply. These drugs have two phosphate groups that cooperate with each other by binding to calcium ions.

Thanks to this, bisphosphonates preferentially bind to this element and accumulate in the bones. They achieve a high concentration in them, while not depositing in other tissues.

Osteoclasts break down bone and release bisphosphonates from the tissue. The drug molecules then penetrate the osteoclast cells. This disrupts the intracellular enzyme functions in the osteoclasts, which leads to the destruction of bone tissue.

Bisphosphonates show a structural similarity to pyrophosphate. Many enzymes are activated by attaching to this chemical. Since the bisphosphonate group mimics the structure of pyrophosphate.

Medicines with it show the ability to imitate this substance. Thanks to this, they combine with the appropriate enzymes, blocking them. It is in this way that bisphosphonates disrupt intracellular processes in osteoclasts.

Bisphosphonates - story

Bisphosphonates were invented and marketed as early as the 19th century. However, they were not used as drugs. The chemical properties of these substances have been used to soften the water in irrigation systems used in orange groves.

The first studies on the use of bisphosphonates in the treatment of bone metabolism disorders date back to the 1960s. The initial rationale for their action in humans was their ability to block the dissolution of hydroxylapatite, which is the main component of the bone mineral.

The actual mechanism of the action of bisphosphates by blocking osteoclasts was not discovered until the 1990s. This was related to the marketing of alendronate.

Bisphosphonates - used in the treatment of osteoporosis

Osteoporosis is a disease in which the bones weaken as a result of a reduction in their mineral density. This increases the risk of fracture. The bones that break the most often include the vertebrae of the spine,forearm and hip bones. Osteoporosis is the most common cause of fractures among the elderly. As a result of this disease, bones can weaken so much that they break spontaneously.

Bisphosphonates are recommended as the most important treatment initiation in the treatment of postmenopausal osteoporosis. Their long-term use in this disease reduces the risk of bone fracture and increases its mineral density.

Biphosphonate therapy lasts five years if given orally, or three years if given intravenously. Treatment effects last for three to five years. Oral therapy for ten years or intravenous therapy for six years is sometimes recommended for those at higher risk.

It is estimated that the use of bisphosphonates reduces the risk of fracture by 25 to 70%. Efficacy depends on the type of bone affected. These drugs are also useful in reducing the risk of future fractures in those patients with a history of osteoporosis.

Bisphosphonates - start of therapy

Proper supply of vitamin D and calcium is essential for maintaining bone density. This element is a very important building component of bone tissue. Vitamin D, on the other hand, is essential to stimulate the proper absorption of calcium.

Before starting treatment involving the intake of bisphosphonates, you should assess the daily intake of calcium in your daily diet, and perform tests for osteomalacia, a disease involving inadequate saturation of the bones with this element. If the results indicate this disorder, an additional vitamin D test should be performed.

If deficiencies are found, be sure to replenish your body's vitamin D and calcium reserves before starting bisphosphonate therapy. Neglecting this problem can lead to fierce symptoms of hypocalcaemia, a condition associated with low blood calcium levels.

Our body has special safeguards that control the levels of elements. When the level of calcium in the blood is low, it is taken from the bones due to the activity of osteoclasts. Bisphosphonates block the breakdown of bone tissue and thus the release of calcium. For this reason, after administering these drugs to a person with low blood levels of this element, it drops even more.

The danger of hypokalemia comes from the fact that calcium is not only a building block of bones. It is also involved in neuromuscular transmission, immune responses and blood clotting. Hypokalaemia which may occur after inappropriate administration of bisphosphonatesleads to symptoms such as:

  • tetany attacks
  • myasthenia gravis
  • gait disturbance

Bisphosphonates in injections and tablets

Bisphosphonates come in the form of oral and intravenous drugs. The advantage of the first option is the ease of administration. For this reason, patients and doctors most often choose tablets. The dose and frequency of its intake is determined by the specialist individually depending on the patient's condition.

The tablet-taking solution has some drawbacks, however. The use of oral bisphosphonates is associated with unpleasant problems on the part of the digestive system.

In order to avoid the previously mentioned side effects, the intravenous form is sometimes used. Its additional advantage is the greater speed of action compared to oral administration. Drugs in this form are usually taken every 3-4 weeks.

Bisphosphonates - it's worth knowing

Bisphosphonates are highly effective drugs. However, it should be remembered that for proper therapeutic effects and minimization of side effects, the correct supply of calcium and vitamin D is important. Therefore, drug therapy should be supplemented with appropriate supplementation.

It is also worth remembering about the influence of these drugs on the ability to concentrate. Taking bisphosphonates may make you feel dizzy and sleepy. Therefore, you should not drive after taking them.

Bisphosphonates - side effects

Orally administered bisphosphonates can cause stomach upset as well as inflammation and erosions of the esophagus. Nausea, vomiting and diarrhea may also occur.

The intravenous forms of these drugs sometimes cause fever and flu-like symptoms. They usually start after the first injection. To reduce these complications, it is recommended that the body be hydrated prior to injection.

About the authorSara Janowska, MA in pharmacyPhD student of interdisciplinary doctoral studies in the field of pharmaceutical and biomedical sciences at the Medical University of Lublin and the Institute of Biotechnology in Białystok. A graduate of pharmaceutical studies at the Medical University of Lublin with a specialization in Plant Medicine. She obtained a master's degree defending a thesis in the field of pharmaceutical botany on the antioxidant properties of extracts obtained from twenty species of mosses. Currently, in his research work, he deals with the synthesis of new anti-cancer substances and the study of their properties on cancer cell lines. For two years she worked as a master of pharmacy in an open pharmacy.

Category:

He alth