Amiodarone values

Aqueous solubility values for the samples analyzed compared favorably with results obtained by traditional methods. The solubility values for amiodarone HC1, reserpine, and benzanthrone were lower than the LOQ of the, uPLC system used for the evaluation. Results of the evaluation of compound solubility employing no-filtration /iPLC were compared with those obtained by two traditional methods (1) multiscreen filtration followed by a UV plate reader, and (2) the shake flask method followed by a UV plate reader. As shown in Figure 6.31, the solubility values determined by the different methods are comparable for most compounds examined. Figure 6.32 shows the results of evaluations of aqueous solubility at four different pH levels for phenazopyridine and piroxicam samples. 

At the cellular level, the major electrophysiological effect appears to be rate-dependent blockade of sodium channels [22]. The onset for this Class I effect (64 + 9% of the final depression of between the first and second beat of the train) was similar to that for Class IB agents [23]. The offset rate (recovery of from rate-dependent depression) for amiodarone was 1.48 s. This value falls between those seen for Class IB agents (200-500 ms) and lA agents (2.3-12.2 s) [23]. Amiodarone inhibited the binding of pH]ba-trochotoxinin A 20a-benzoate to the sodium channel, suggesting that it binds to inactivated sodium channels [24]. 

A 38-year-old man, who had taken amiodarone 200 mg/day for more than 6 months, was given postexposure prophylaxis for HIV infection after a needle injury this included zidovudine, lamivudine, and indinavir (256). During the 4 weeks of therapy his serum amiodarone concentration rose from 0.9 to 1.3 mg/1, with only a small rise in the serum concentration of desethylamiodarone from 0.4 to 0.5 mg/1. After withdrawal of the prophylactic therapy the plasma amiodarone concentration gradually fell to the pretreatment value, and there was no further change in the concentration of desethylamiodarone. 

In one careful study EC50 values for certain effects of amiodarone were calculated (269). The respective concentrations of amiodarone and desethylamiodarone that were associated with effects were as follows reduction in heart rate 1.2 and 0.5 mg/ml QTc prolongation 2.6 and 1.4 mg/ml corneal microdeposits 2.2 and 1.1 mg/ml. 

Maury P, Zimmermann M, Metzger J, Reynard C, Dorsaz P, Adamec R. Amiodarone therapy for sustained ventricular tachycardia after myocardial infarction long-term followup, risk assessment and predictive value of programmed ventricular stimulation. Int J Cardiol 2000 76(2-3) 199-210. 

Nicholson AA, Hayward C. The value of computed tomography in the diagnosis of amiodarone-induced pulmonary toxicity. Clin Radiol 1989 40(6) 564-7. 

Belhassen A, Vaksmann G, Francart C, Vinatier D, Patey P, Monnier JC. Interet de I amiodarone dans le traitement des tachycardies supraventriculaires foetales. A propos d une observation. [Value of amiodarone in the treatment of fetal supraventricular tachycardia. Apropos of a case.) J Gynecol Obstet Biol Reprod (Paris) 1987 16(6) 795-800. 

M KCl were performed on the PCA 101 titrator. .. at 25 °C for amiodarone, metoprolol and ramipril and at 37 °C for atenolol. The pKa values of metoprolol, atenolol, and ramipril were determined in 0.15M KCl. For die extrapolation of the aqueous pKa of amiodarone, we used the Yasuda-Shedlovsky plot (4). Apparent pKa values (+ log [H2O]) in the medianol/O.lSM KCl mixtures at ratios between 47 and 71%(w/w) methanol were plotted against the inverse dielectric constant... and the pKa of the molecule in 100% aqueous solution was extrapolated by linear regression." surface H2O Ferreira J, Brasseur R, Chatelain P and Ruysschaest J, Properties of... 

However, in 1998 the manufacturers of lansoprazole had on record two reports of possible interactions. An elderly patient taking warfarin developed an INR of 7 when lansoprazole was added. Despite a warfarin dosage adjustment he had a gastrointestinal haemorrhage, a myocardial infarction and died after 3 weeks. Another man taking warfarin (as well as amiodarone, furosemide and lisinopril) became confused, had hallucinations and developed an increased INR (value not known) when given lansoprazole. The lansoprazole was stopped after 4 days, and he then recovered. However, it is uncertain whether this was an interaction or whether he had taken an incorrect warfarin dosage because of his confusion. ... 

A Caucasian female was diagnosed with bronchiolitis obliterans organising pneumonia (BOOP)-like interstitial pneumonia (transbronchial lung biopsy) after 9 months of PTU therapy for amiodarone-induced TTX (thyroidihs without nodules). Values for antinuclear antibody (ANA) and ANCA were negative and tiie BOOP-like interstitial pneumonia was resolved after discontinuation of PTU. 

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