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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.

Background: Enemas are used by individuals with constipation and are of-ten required before certain medical diagnostic procedures and surgical interventions. However, abnormalities in serum electrolyte concentrations have been associated with enema use.Objective: The aim of this study was to determine the changes in serum electrolyte concentrations (phosphorus, calcium, sodium, and potassium) and urinary phosphorus elimination after the administration of a sodium phosphate enema.Methods: Healthy volunteers aged 35 to 70 years were eligible for this open-label, randomized, controlled, 2-period, crossover clinical trial at the Clinical Research Unit of the University Hospital of Navarra, Pamplona, Spain. The study comprised 2 one-day periods separated by a 7-day washout. All subjects were randomly assigned in a 1:1 ratio to 1 of 2 study sequences: (1) a single dose of Enema Cased 250 mL in the first period followed by no treatment (control) in the second period, or (2) no treatment in the first period followed by a single dose of the study drug in the second period. The sequence of treatment was assigned using a randomization table that was prepared before the beginning of the study. Serum concentrations of phosphorus, sodium, potassium, and calcium were measured in both periods. Urinary phosphorus elimination was measured for 12 hours after enema administration (Ae[0-12]) in a subset of the subjects in the second period. Adverse events (AEs) were monitored by the investigators throughout the study. Normal ranges for the electrolytes were as follows: phosphorus, 2.5 to 5 mg/dL; calcium, 8.5 to 10.5 mg/dL; sodium, 135 to 145 mEq/L; and potassium, 3.5 to 5 mEq/L.Results: Twenty-four subjects (12 men, 12 women; mean [SD] age, 47.8 [9.6] years [range, 36-68 years]) participated in the study. All of the subjects were white and none were smokers. Twelve hours after enema administration, mean serum phosphorus and sodium concentrations increased by a mean of 1.18 mg/dL and 1.32 mEq/L, respectively (both, P < 0.001). Mean serum phosphorus concentrations were above the upper limit of normal (5 mg/dL) at 30 and 60 minutes after enema administration. In all subjects the values returned to normal within 4 hours after enema administration; a meal was provided after a 3-hour fast. Four subjects (16.7%) had >/=>1 serum phosphorus concentration measurement >/=7 mg/dL, a value that is considered serious hyperphosphatemia. A statistically significant correlation was found between phosphorus [C][max] and enema retention time (r[2] = 0.452; P < 0.001). No abnormal serum concentrations were obtained for the other electrolytes measured. Phosphorus Ae[0-12] was increased after enema administration by 86% (P < 0.001). No serious AEs were observed, although 13 AEs were reported in 9 subjects. None of the changes in serum electrolyte concentrations were associated with clinical symptoms.Conclusions: Administration of an enema containing 250 mL of sodium phosphate was associated with serum phosphorus concentrations of >/=7 mg/dL in 16.7% of the healthy subjects who participated in the study; however, none of those subjects experienced hypocalcemia. Enema retention time was significantly correlated with the degree of phosphatemia. [ABSTRACT FROM AUTHOR]

Azole antifungals have different pharmacokinetic characteristics: complete oral absorption for Voriconazole, and to a lesser extent for fluconazole. The absorption of posaconazole and itraconazole increases with food intake. All of them have high tissue distribution with low plasma concentrations, especially low in the case of posaconazole and itraconazole. Posaconazole and itraconazole have high plasmatic protein binding and consequently both have a very low free fraction. Elimination of azole antifungals is through a metabolic pathway with CYP450 isoenzymes, and has a non linear pharmacokinetics with a high risk of interation with other drugs since azoles have the ability of CYP450 isoenzymes inhibition. Possibly the parameter that defines more precisely their efficacy is AUIC with an optimum value near 20, although cut-off values must be defined since some azoles may have difficulty to reach this value.