ABSTRACT
Twenty-one elderly patients with chronic brain failure received a single 30 mg oral dose of the calcium channel blocker nimodipine followed by two weeks of 30 mg three times a day (t.i.d.) administration. The aim of this study was to assess if drug accumulation occurred in our frail elderly subjects under this dose regimen. Plasma concentrations of nimodipine and three main metabolites were determined by gas chromatography. During the 2-week period we did not find significant changes in peak plasma concentrations and corresponding areas under the plasma concentration-time curves. Trough nimodipine plasma concentrations before administration of the morning dose were similar on days 7 and 14. Therefore, no evidence of drug accumulation was found. Blood pressure and heart rate remained stable throughout the study period and no adverse effects were observed. During the study period, there was a decline in the proportion of patients who complained about dizziness and insomnia. Overall, our data suggest that there is no need to alter the usual adult dose of nimodipine if this drug is administered to multimorbid frail elderly patients suffering from chronic brain failure.
ABSTRACT
The serum levels of tiaprofenic acid were determined by HPLC in 20 geriatric patients with ischemic heart disease, and the pharmacokinetic parameters were calculated. The results indicate that in geriatric patients the drug does not accumulate when given at a dose of 300 mg twice a day. Sufficient plasma levels are reached and the short terminal phase half-life prevents accumulation. The electrolyte balance was examined during the 7 days of treatment, and no change in sodium and potassium levels in the serum or in urine were observed. Weight as well as blood pressure of the patients remained constant, so that an increased development of edema, especially with regard to the existing ischemic heart disease of the patients, could be excluded. The results of our study indicate that tiaprofenic acid at the employed dosage is suitable for the therapy of arthritis in geriatric patients suffering from ischemic heart disease, without accumulation of the drug or the development of edema.
Subject(s)
Aging/metabolism , Anti-Inflammatory Agents, Non-Steroidal/pharmacokinetics , Coronary Disease/metabolism , Propionates/pharmacokinetics , Aged , Aged, 80 and over , Anti-Inflammatory Agents, Non-Steroidal/blood , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Female , Humans , Inflammation/drug therapy , Male , Potassium/blood , Potassium/urine , Propionates/blood , Propionates/pharmacology , Sodium/blood , Sodium/urine , Water-Electrolyte Balance/drug effectsABSTRACT
Ranitidine pharmacokinetics was measured after intravenous administration of 50 mg of the drug in 18 geriatric patients suffering from multiple diseases. Elimination half-life was prolonged (3.05 +/- 0.58 h) and total clearance was reduced (282 +/- 97 ml/min) as compared to the results of studies on normal younger persons by other investigators. In comparison to other studies on healthy elderlies, the pharmacokinetic parameters of ranitidine were only slightly different. Statistical analyses showed correlations of pharmacokinetic parameters of ranitidine with creatinine clearance, serum creatinine, uric acid concentration and alkaline phosphatase activity. These results disclose that reduced creatinine clearance or serum creatinine concentration in the upper normal range, for example, might serve as indicators for a possible dose reduction of ranitidine to prevent unnecessary overmedication in elderly patients.
Subject(s)
Aging/metabolism , Cerebrovascular Disorders/metabolism , Coronary Disease/metabolism , Diabetes Mellitus/metabolism , Ranitidine/pharmacokinetics , Aged , Aged, 80 and over , Cerebrovascular Disorders/complications , Coronary Disease/complications , Creatinine/metabolism , Diabetes Complications , Female , Humans , Infusions, Intravenous , Male , Peptic Ulcer/complications , Peptic Ulcer/drug therapy , Peptic Ulcer/metabolism , Ranitidine/blood , Ranitidine/pharmacology , Stress, PhysiologicalSubject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacokinetics , Propionates/pharmacokinetics , Aged , Aged, 80 and over , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Female , Humans , Intestinal Absorption , Male , Osteoarthritis/complications , Osteoarthritis/drug therapy , Osteoarthritis/metabolism , Propionates/therapeutic useABSTRACT
Haemoglobin Haptoglobin complexes formed when [Hp+]/[Hb]= 1/1 and [Hp]/[Hb] =2/1 were investigated by 57Fe Mössbauer spectroscopy. Both samples gave a spectrum consisting of a single quadrupole doublet. The temperature dependence of the quadrupole splitting was also identical for both samples. This proves that in both samples the nearest neighbour environment of the iron atom must be the same. A comparison with earlier investigations on myoglobin and haemoglobin indicates that the electronic structure of iron in the HbHp-complexes is similar to that in myoglobin.
Subject(s)
Haptoglobins , Hemoglobins , Cold Temperature , Spectrometry, GammaABSTRACT
The electronic term scheme of ferric iron in metmyoglobin, metmyoglobin fluoride, and methemoglobin is evaluated by a Hamiltonian which involves the Coulomb repulsion of the 3d electrons, their interaction with the C2v-coordinated ligands, and spin-orbit coupling. The adjustable parameters of the theory were determined by a least squares fit to experimental EPR, susceptibility, and far-infrared data reported in the literature. According to these results, the structural properties of the ferric ion and its neighboring ligands were discussed by means of group theoretical arguments: An increasing out of plane position of the ferric ion is found in the sequence metHb--metMb--MbF which corresponds to an increasing binding strength with the axial ligands.
