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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">nnp</journal-id><journal-title-group><journal-title xml:lang="en">Neurology, Neuropsychiatry, Psychosomatics</journal-title><trans-title-group xml:lang="ru"><trans-title>Неврология, нейропсихиатрия, психосоматика</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2074-2711</issn><issn pub-type="epub">2310-1342</issn><publisher><publisher-name>"IMA-Press", LLC</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.14412/20742711-2021-4-109-115</article-id><article-id custom-type="elpub" pub-id-type="custom">nnp-1624</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>REVIEWS</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>ОБЗОРЫ</subject></subj-group></article-categories><title-group><article-title>Oral administration of cyanocobalamin for functional vitamin В12 deficiency: efficacy and safety</article-title><trans-title-group xml:lang="ru"><trans-title>Пероральное применение цианокобаламина при функциональном дефиците витамина В12: эффективность и безопасность</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Ших</surname><given-names>Е. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Shikh</surname><given-names>E. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Ших Евгения Валерьевна.</p><p>119991, Москва, ул. Трубецкая, 8, стр. 2.</p></bio><bio xml:lang="en"><p>Evgeniya Valerievna Shikh.</p><p>8, Trubetskaya St., Build. 2, Moscow 119991.</p></bio><email xlink:type="simple">chih@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Сизова</surname><given-names>Ж. М.</given-names></name><name name-style="western" xml:lang="en"><surname>Sizova</surname><given-names>Zh. M.</given-names></name></name-alternatives><bio xml:lang="ru"><p>117418, Москва, Нахимовский проспект, 49.</p></bio><bio xml:lang="en"><p>49, Nakhimovsky prospect, Moscow 117418.</p></bio><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Астаева</surname><given-names>М. О.</given-names></name><name name-style="western" xml:lang="en"><surname>Astaeva</surname><given-names>M. O.</given-names></name></name-alternatives><bio xml:lang="ru"><p>119991, Москва, ул. Трубецкая, 8, стр. 2.</p></bio><bio xml:lang="en"><p>8, Trubetskaya St., Build. 2, Moscow 119991.</p></bio><xref ref-type="aff" rid="aff-3"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Кафедра клинической фармакологии и пропедевтики внутренних болезней Института клинической медицины им. Н.В. Склифосовского</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Department of Clinical Pharmacology and Internal Diseases Propedeutic, N.V. Sklifosovsky Institute of Clinical Medicine</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>Кафедра медико-социальной экспертизы, неотложной и поликлинической терапии Института профессионального образования;</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Department of Medical and Social Expertise, Emergency and Polyclinic Therapy, Institute of Professional Education</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-3"><aff xml:lang="ru"><institution>Институт клинической медицины им. Н.В. Склифосовского, Первый Московский государственный медицинский университет им. И.М. Сеченова Минздрава России (Сеченовский Университет)</institution><country>Россия</country></aff><aff xml:lang="en"><institution>N.V. Sklifosovsky Institute of Clinical Medicine, I.M. Sechenov First Moscow State Medical University (Sechenov University), Ministry of Health of Russia</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2021</year></pub-date><pub-date pub-type="epub"><day>14</day><month>08</month><year>2021</year></pub-date><volume>13</volume><issue>4</issue><fpage>109</fpage><lpage>115</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Shikh E.V., Sizova Z.M., Astaeva M.O., 2021</copyright-statement><copyright-year>2021</copyright-year><copyright-holder xml:lang="ru">Ших Е.В., Сизова Ж.М., Астаева М.О.</copyright-holder><copyright-holder xml:lang="en">Shikh E.V., Sizova Z.M., Astaeva M.O.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://nnp.ima-press.net/nnp/article/view/1624">https://nnp.ima-press.net/nnp/article/view/1624</self-uri><abstract><p>The prevalence of vitamin В12 deficiency is about 3—16% in the general population, while in older people, it ranges from 10 to 20%. An increase in the proportion of people on reduced-calorie diets, the widespread use of drugs that can result in vitamin В12 deficiency, an increase in life expectancy, on the one hand, a variety of clinical manifestations and the lack of precise algorithms for laboratory diagnostics, on the other hand, suggest that the number of patients with vitamin В12 deficiency is significantly higher. Vitamin В12 can be absorbed by passive diffusion, regardless of intrinsic factor and other underlying causes of the deficiency. The presence of an additional route of absorption brings in new expectations for the oral administration of cyanocobalamin in therapeutic doses. Comparative clinical trials of the use of cyanocobalamin have shown that the oral route of administration is as effective as the parenteral. Considering the need for long-term, and in some cases — life-long, use of the drug, there is a need to develop dosage regimens for oral administration comparable in effectiveness to parenteral administration. The use of functional vitamin В12 deficiency biomarkers, such as vitamin В12 levels, cholotranscobalamin, methylmalonic acid, homocysteine, made it possible to establish that a daily dose of 1000 mkg is the most effective, which at the initial stage is as efficient as intramuscular administration. In some circumstances, maintenance therapy (intramuscularly at a dose of 1 mg/month) was more effective; thus, a differentiated approach scheme to determining the maintenance oral dose was proposed, depending on the result obtained at the initial stage of therapy. Comparative studies covering the entire spectrum from the recommended dietary allowance to the dose commonly used for cobalamin injections have shown that an oral daily dose of 1000 mcg of cyanocobalamin normalizes serum vitamin В12 levels and causes an 80—90% decrease in plasma methylmalonic acid concentration from the assumed maximum value. The oral route of administration provides a higher patient treatment adherence.</p></abstract><trans-abstract xml:lang="ru"><p>Распространенность дефицита витамина В12 среди населения оценивается примерно на уровне 3—16%, при этом у пожилых людей она колеблется в диапазоне от 10 до 20%. Повышение доли лиц, использующих редукционные диеты, широкое применение лекарственных средств, результатом взаимодействия с которыми становится дефицит витамина В12, увеличение продолжительности жизни, с одной стороны, разнообразие клинических проявлений и отсутствие четких алгоритмов лабораторной диагностики — с другой стороны, позволяют предположить, что число пациентов с дефицитом витамина В12 существенно выше. Витамин В12 может абсорбироваться путем пассивной диффузии, независимо от внутреннего фактора и других основных причин дефицита. Наличие дополнительного пути всасывания открывает перспективы использования лечебных доз цианокобаламина перорально (п/о). Сравнительные клинические исследования применения цианокобаламина показали не меньшую эффективность п/о пути введения по сравнению с парентеральным. Учитывая необходимость длительного, а в ряде случаев — пожизненного применения препарата, актуальной является разработка режимов дозирования п/о лекарственных форм, сопоставимых по эффективности с формами для парентерального введения. Применение биомаркеров функционального дефицита витамина В12, таких как определение уровней витамина В12, холотранскобаламина, метилмалоновой кислоты, гомоцистеина, позволило установить, что наиболее эффективной является суточная доза 1000 мкг, которая на стартовом этапе не уступает по эффективности внутримышечному введению. В ряде случаев поддерживающая терапия (внутримышечно в дозе 1 мг/мес) была более эффективной, в связи с чем предложена схема дифференцированного подхода к определению величины поддерживающей п/о дозы в зависимости от результата, полученного на стартовом этапе терапии. В сравнительных исследованиях, охватывающих весь возможный спектр от рекомендуемой диетической нормы до обычно используемой при инъекциях кобаламина дозы, показано, что п/о суточная доза 1000 мкг цианокобаламина нормализует уровень витамина В12 в сыворотке крови и вызывает снижение концентрации метилмалоновой кислоты в плазме крови на 80—90% от предполагаемого максимального значения. П/о путь применения обеспечивает более высокую приверженность пациентов лечению.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>цианокобаламин</kwd><kwd>дефицит</kwd><kwd>пероральный прием</kwd><kwd>ятрогения</kwd><kwd>витамин В12</kwd><kwd>холотранскобаламин</kwd><kwd>метилмалоновая кислота</kwd></kwd-group><kwd-group xml:lang="en"><kwd>cyanocobalamin</kwd><kwd>deficiency</kwd><kwd>oral administration</kwd><kwd>iatrogeny</kwd><kwd>vitamin В12</kwd><kwd>holotranscobalamin</kwd><kwd>methylmalonic acid</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Статья спонсируется компанией «Верваг Фарма».</funding-statement><funding-statement xml:lang="en">This article has been supported Woerwagpharma.</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Andres E, Dali-Youcef N, Vogel T, et al. Oral cobalamin (vitamin B(12)) treatment. An update. 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