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La mayoría de los ciudadanos europeos no cumplen con un adecuado aporte de calcio y vitamina D en sus dietas, por lo que los suplementos de ambos pueden ayudar a cubrir las necesidades. El déficit de vitamina D puede conducir a una menor absorción de calcio, un aumento del remodelado óseo y un incremento de la pérdida de masa ósea; además, el déficit de vitamina D reduce la función muscular y aumenta el riesgo de caidas. El carbonato de calcio es la forma farmacéutica de uso más común, debido a su perfil coste/eficacia, de administrar suplementos de calcio en nuestro medio. Otras sales como el lactato y gluconato presentan una menor concentración del elemento y son poco prácticas. El objeto del presente artículo es poner de manifiesto la relevancia de la asociación calcio-vitamina D, su protagonismo en la prevención y tratamiento de la osteoporosis, así como las formas farmacéuticas más frecuentes y útiles para su uso clínico.

Sepsis represents a serious risk to the life of any patient, which is why it is crucial to start an effective treatment in all its extremes as soon as possible, that is, the chosen antibiotics must have activity against the pathogen that produces the condition and, in addition, they must be dosed considering the patient's situation in all its extremes. It should be considered that it will be necessary to adjust the dose when there is edema (drugs with reduced volume of distribution), hypoproteinemia (drugs bound to proteins in a high proportion), obesity, and also when they require the use of external techniques such as ECMO or any of the different types of hemodialysis and hemofiltration., (©The Author 2022. Published by Sociedad Española de Quimioterapia. This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)(https://creativecommons.org/licenses/by-nc/4.0/).)

Cefiderocol is a new cephalosporin with a catechol in its chemical structure faciliting its access to the interior of bacteria through iron channels. In addition, it is broadly stable to beta-lactamases. The pharmacokinetic profile is a beta-lactam one: no oral absorption, and with a wide distribution within the vascular space and the interstitial fluid of well vascularized tissues, reaching therapeutic concentrations in the alveolar lavage fluid and within the macrophage. The binding of cefiderocol to human plasma proteins, primarily albumin, is moderate (range 40-60%). The terminal elimination half-life in healthy adult subjects was 2 to 3 hours. Cefiderocol is mainly renally eliminated, so dose adjustments are recommended in subjects with moderate / severe renal impairment, in case of dialysis, and probably in patients with external clearance. Like other beta-lactams, the PK / PD parameter that has been shown to best correlate with efficacy is the efficacy time of unbound plasma concentrations (%fT>MIC), which must be close to 100% to achieve a bactericidal effect. This is possible with 2 g in a 3-hour infusion every 8 hours. In controlled trials appears to be well tolerated, similar to comparators: meropenem or imipenem-cilastatin. Cefiderocol has no apparent clinically significant effect on ECG parameters nor on plasma iron values., (©The Author 2022. Published by Sociedad Española de Quimioterapia. This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)(https://creativecommons.org/licenses/by-nc/4.0/).)

Liposomal amphotericin B is a lipid formulation of the antifungal drug amphotericin B with some distinguishing characteristics in its pharmacological behavior that entail some clinical differences of great interest. The significant improvement in the systemic and renal tolerability is one of them. This fact is related to the great stability of the liposome, promoted by its negative charge, the presence of cholesterol and the remarkable thermo-stability of the remaining lipids that compose it. In this situation, amphotericin B seems to be released from the liposome not spontaneously but when the liposome binds to the ergosterol in the fungal cell membrane. For this reason, there is almost no free amphotericin B in plasma or tissues, although it seems that its availability is greater when there is fungal infection. As a consequence, when the pharmacokinetic behavior is studied, the concentration and availability of liposomal amphotericin B are very high, and its volume of distribution is reduced in comparison with the other formulations., (Copyright © 2021 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.)

Ceftobiprole shows many similar pharmacokinetic properties to other cephalosporins, except for not being orally bioactive, and that it is administered by IV infusion as the prodrug ceftobiprole medocaril, which is subsequently hydrolyzed in the blood into the active molecule. Distribution focus in extracellular fluid and active antibiotic concentration has been proven in different corporal tissues using dosing regimen of 500 mg intravenous infusion over 2 h every 8 h. Ceftobiprole is eliminated exclusively into the urine, thus the reason why dose adjustment is required for patients with moderate or severe renal impairment, or increased creatinine clearance. However, there is no need for dose adjustments related with other comorbidities and patients' conditions such as age, body weight. Although considering distribution features, molecular weight and dose fraction, increase dosing regimen might be necessary in patients using renal replacement therapy. The half-life of ceftobiprole is more than 3 h, allowing to easily reach optimal PK/PD parameters with the infusion time of 2 h, using the usual dosing regimen.

Objective: To describe the pharmacokinetic (PK) profile of anidulafungin and to evaluate its concentration in the peritoneal fluid (PF) of patients suspected of suffering from peritoneal infection undergoing abdominal surgery, in order to ensure that therapeutic levels are achieved within the peritoneal cavity., Methods: A descriptive, open, prospective, observational, multicentre and non-interventional study was performed. Anidulafungin was used at conventional doses. Blood and PF samples were obtained on day 2 of treatment or on any of the following days., Results: A total of 31 patients in a serious clinical condition, as demonstrated by high mean clinical severity scale scores (APACHE II and SOFA scores), were included in the study. The mean area under the curve (AUC) in PF was 30% (31±19%) of that determined in the plasma and the maximum concentration (Cmax) reached in PF (mg/l) was close to 1 (0.9±0.5). No adverse effects were observed in any of the 31 patients., Conclusions: Anidulafungin at conventional doses reaches PF concentrations that exceed the minimum inhibitory concentration of the usual Candida spp, which explains the proven efficacy of this echinocandin in the treatment of Candida peritonitis in critically ill patients., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

In the past, the dose of an antibiotic was chosen, always from among those that were well tolerated, by considering those with the ability to exceed the MIC of bacteria in plasma. This approach, which has still not widely changed, is contrast-ed with the pharmacokinetic and pharmacodynamic (PK/PD) relationships, which indicate that the efficacy of antibiotics is directly related to parameters that relate the sequence of con-centrations over time with a parameter of the MIC effect in vitro. Until now, three types of PK/PD relationships have been established for antibiotics: the inhibitory coefficient (Cmax/MIC), the efficacy time (T>CMI) and the relationship between the exposure of the drug and the MIC (AUC/MIC).

Isavuconazole is a new azole, structurally related to fluconazole and voriconazole, that presents a very high oral absorption with no first-pass effect which is not interfered by the presence of food, gastric pH modifications, or mucositis. Its distribution volume is very high, probably also to cerebrospinal fluid, in spite of the fact that it circulates highly bound to plasma proteins. It is extensively metabolized through the CYP3A4 isoenzyme. Due to this reason, it is recommended to avoid co-administration with strong CYP3A4 inducers. In addition, isavuconazole may inhibit CYP3A4. Moreover, it may induce CYP2B6 and P-glycoprotein. Interestingly, this inhibitory activity seems to be lower compared to other azoles. Therefore, the management of any interaction with other medicines is easier, which is probably the most important advantage of this antifungal., (Copyright © 2018 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.)

The echinocandins share pharmacodynamic properties, although there are some interesting differences in their pharmacokinetic behaviour in the clinical practice. They are not absorbed by the oral route. They have a somewhat special distribution in the organism, as some of them can reach high intracellular concentrations while, with some others, the concentration is reduced. They are highly bound to plasma proteins, thus it is recommended to administer a loading dose for anidulafungin and caspofungin, although this procedure is not yet clear with micafungin. Echinocandins are excreted via a non-microsomal metabolism, so the urinary concentration is very low. Some carrier proteins that take part in the biliary clearance process are probably involved in the interactions described with caspofungin and micafungin. These two drugs must be used with caution in patients with severely impaired hepatic function, while all of them can be used without special precautions when there is renal impairment or the patient requires renal replacement therapy., (Copyright © 2016 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.)

Objective: Infectious complications are an important cause of morbidity and mortality in haematological patients with febrile neutropenia. The aim of this study was to develop a consensus document of recommendations to optimize the management of febrile neutropenic patients with haematological or vascular catheter infections in areas where there is no solid scientific evidence., Methods: After reviewing the scientific evidence, a scientific committee composed of experts in haematology and infectious diseases developed a survey with 55 statements. A two- round modified Delphi method was used to achieve consensus., Results: The online survey was answered by 52 experts in the field of haematology and infectious diseases. After two rounds of evaluation, a consensus was possible in 43 of the 55 statements (78.2%): 40 in agreement and 3 in disagreement. Recommendations are given related to empirical antibiotic treatment of patients with febrile neutropenia, mechanisms of action, toxicity and synergism of antibiotics in this context, modifications of antibiotic treatment in the course of febrile neutropenia, and the management of central vascular catheter infections in the haematological setting., Conclusions: There is a high degree of agreement among experts on some controversial issues concerning the management of febrile neutropenia and catheter infection in hematologic patients. This agreement has resulted in recommendations that may be useful in clinical practice.

Aflibercept is a fusion protein whose chemical structure combines the constant fraction of any IgG with a variable fraction constructed with fundamental parts of VEGF receptors. Consequently, it is able to bind to various VEGF as well as to placental growth factor (PIGF), which has been related to a possible synergistic effect in efficacy. The affinity of this drug is higher than that of ranibizumab and bevacizumab. Moreover, it has an intraocular antiinflammatory effect. Intravitreal administration leads to the presence of traces of the drug in plasma but the concentrations are so reduced that the presence of systemic adverse effects, including arterial hypertension, is practically nil. Because of its prolonged intraocular elimination half-life and high affinity, the drug can be administered in convenient regimens, since, after an initial monthly injection for the first three doses, the interval between injections is increased to one every two months and, after the first 12 months, the dosing will depend on the visual and anatomical results., (Copyright © 2015 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.)

Bevacizumab is able to cross ocular barriers when administered through the intravitreal route and to generate plasma concentrations with an inhibitory effect on plasma vascular endothelial growth factor (VEGF). Consequently, systemic effects cannot be ruled out. The fact that bevacizumab is a full-length IgG explains this phenomenon through the participation of FcRn receptors, whose binding-like that of all IgGs-implies their internalization, transfer to the cell membrane, and externalization to the intracellular space and blood. This process occurs in all tissues with cells expressing this type of receptor, such as the eye. Moreover, because of the absence of a specific formulation for intravitreal administration, an intravenous formulation must be manipulated, generating large-sized aggregates, leading to potential problems of the solution's sterility and reducing the pharmacological effect. Ranibizumab is not a full-length IgG but is rather a variable IgG fraction with anti-VEGF activity. Because of the absence of a constant fraction in its structure, this drug cannot bind to the FcRn receptor and, as a result, cannot be transported to the blood. Consequently, its systemic bioavailability after intravitreal administration is nil, thus avoiding effects in parts of the body other than the eye. Moreover, the formulation is specifically prepared for intraocular administration, avoiding problems due to manipulation. The experience gained with these drugs allows the differences in their efficacy and tolerability to be transferred to daily practice., (Copyright © 2012 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.)

Amphotericin B in its lipid formulation continues to be the reference drug in the treatment of systemic fungal infections despite the time elapse since the development of this compound. The absence of fungal resistance, pharmacokinetics, and the better tolerability profile as compared with the remaining formulations of amphotericin B are sufficient reasons to justify its prominent therapeutic role. The liposome containing liposomal amphotericin B is very stable in relation to the presence of cholesterol and phospholipids are not thermolabile, so that free amphotericin B is almost inexistent (<1%), which explains the reduced incidence of effects related to the drug administration, and a reduction in the incidence of nephrotoxicity (half than that with amphotericin B lipid complex) and that even in some studies at doses of 1 mg/kg has been shown to be negligible. This profile explains the very high plasma drug concentrations and the reduced distribution volume and clearance, with a very prolonged elimination half-life. There are evidences showing that the liposome through amphotericin B is capable of binding to ergosterol present in the fungal membrane and only at this moment would be the antifungal released to exert its pharmacological effects.

Bilastine is a potent inhibitor of the histamine H1 receptor. It was recently approved in 28 countries of the European Union for the symptomatic treatment of allergic rhinoconjunctivitis and urticaria in adults and children older than 12 years. Data from preclinical studies confirmed its selectivity for the histamine H1 receptor over other receptors, and demonstrated antihistaminic and antiallergic properties in vivo. Studies in healthy volunteers and patients have shown that bilastine does not affect driving ability, cardiac conduction or alertness. Bilastine has demonstrated a good safety profile, without serious adverse effects or antimuscarinic effects in clinical trials. There were no significant changes in laboratory tests, electrocardiograms or vital signs. In clinical studies, oral treatment with bilastine 20 mg once daily improved allergic rhinitis with greater efficacy than placebo and comparable to cetirizine and desloratadine. Bilastine 20 mg was more effective than placebo and equivalent to levocetirizine in chronic urticaria, relieving symptoms, improving quality of life and controlling sleep disorders., (2011 Prous Science, S.A.U. or its licensors. All rights reserved.)

The objective of the present article is the review of the most important therapeutic innovations in the treatment of multiple myeloma in terms of efficacy and cost-effectiveness. Besides autologous transplant with peripheral-blood stem-cell, thalidomide establishes as one of the most powerful therapeutic tools in induction and maintenance treatment and together with lenalidomide and bortezomib as therapy for relapsing/refractory multiple myeloma. Considering, the last named situation thalidomide can be an adequate therapeutical option in combination with dexamethasone. Under a strictly pharmacoeconomic point of view, lenalidomide and bortezomib seem to be additional alternatives in patients previously treated with thalidomide.

Introduction: A short antibiotic regimen is recommended for the treatment of uncomplicated lower urinary tract infection. Nevertheless, the treatment to follow in other situations is not so clearly defined. When the person affected by lower urinary tract infection is not a young woman, it is recommended to treat at least 7 days, and quinolones or cotrimoxazole are the antibiotics most often used. However, because of the frequency of drug resistance in this type if infection, it is advisable to apply antibiotics with lower rates of resistance, such as fosfomycin trometamol, for longer treatment periods than the often-used single dose., Methods: Using the data on urinary elimination of fosfomycin after a single dose obtained in a prior study in healthy volunteers, we simulated the urinary concentrations of this antibiotic following administration of two doses. In addition, we calculated the interval of administration required to achieve urinary concentrations greater than 16 mg/L, the critical concentration of sensitivity for Escherichia coli, one of the most commonly implicated microorganisms in these infections., Results: Fosfomycin concentrations in urine persisted above the defined cut-off for 161 hours after administration of two 3-g doses of fosfomycin trometamol, 72 hours apart. This implied an efficacy time of 66% in a period of 7 days., Conclusion: From the pharmacokinetic viewpoint, the optimum dosage of fosfomycin trometamol to achieve appropriate urinary concentrations along 7 days is administration of two 3-g doses, 72 hours apart.

Antimicrobials with specific activity against Gram-positive cocci (glycopeptides, oxazolidinones and streptogramins) have pharmacokinetic differences that are important to know. Linezolid and teicoplanin can be administered extravascularly due to their good bioavailability, allowing their use as sequential therapy in patients requiring prolonged treatment. All of these antimicrobials have an adequate distribution in extracellular tissues, even teicoplanin, due to the balance between the fraction that is bound and unbound to plasma proteins and its long terminal half-life. As the elimination of glycopeptides is almost exclusively renal, it is necessary to perform a posology adjustment in patients with renal failure. Quinupristin/dalfopristin and linezolid are metabolized by the liver, but CYP450 is only involved in streptogramin elimination.

Pirozadil and alufibrate are compared by a single-blind study over two groups 20 patients with primary hyperlipoproteinemia. Pirozadil seems more effective as a cholesterol-lowering agent. There were no adverse reactions. We conclude that pirozadil can be a valuable agent in preventing atherosclerotic disease.