1. Drug data coding and analysis in epidemiologic studies
M. Pahor, E.A. Chrischilles, J.M. Guralnik, S.L. Brown, R.B. Wallace & Pierugo Carbonin. European Journal of Epidemiology 10: 405-411, 1994.
EPESE study. At baseline interview, drug data information was obtained from 3467 participants of the Iowa EPESE site for whom face-to-face interviews were conducted. Overall, 11,750 ingredients of 9,955 drug products were taken by the study participants. The first 2 hierarchical levels of IDIS code (first 4 digits) allowed us to identify all diuretics (code: 4028, electrolyte solutions-diuretics, n = 1447 ingredients) (Table 1). According to the IDIS classification there were 15 different diuretic ingredients divided in 3 categories taken by the study population. The first category (3rd hierarchical level of IDIS code: 402800) contained 3 potassium-sparing diuretics (n = 213): spironolactone, triamterene and amiloride. Low-ceiling diuretics were included in the second category (3rd hierarchical level of IDIS code: 402801): 8 thiazide diuretic ingredients (n = 941) (bendroflumethiazide, chlorothiazide, hydrochlorothiazide, benzthiazide, hydroflumethiazide, methyclothiazide, polythiazide, and trichlomethiazide) and 3 sulfonamide derivatives (chlorthalidone, metolazone and quinethazone). The loop-diuretics category (n = 214) (3rd hierarchical level of IDIS code: 402804) contained only 1 ingredient: furosemide (bumetanide was not marketed in the USA in 1980). In the last column of Table 1 are shown the frequencies of diuretic ingredients combined with other drug ingredients within the same drug product. Table 2 describes in detail those combinations and their frequencies.
2. The Science of USP 1 and 2 Dissolution: Present Challenges and Future Relevance
Vivian Gray, Gregg Kelly, Min Xia, Chris Butler, Saji Thomas, and Stephen Mayock. Pharmaceutical Research, Vol. 26, No. 6, June 2009
The effect of powder substrate composition on the dissolution rate of methyclothiazide liquisolid compacts was illustrated by Spireas et al.. Dissolution rates were increased by optimizing carrier-to-coating ratios in methyclothiazide liquisolid tablets containing a 5% w/w drug solution in polyethylene glycol 400 with difference excipient ratios. The dissolution conditions used were the paddle at 50 rpm and a medium of 0.1 N hydrochloric acid. The influence of excipients, especially binders, on the dissolution rate of paracetamol tablet formulations was shown by Abebayo et al.. The effect of binders, namely breadfruit and cocoyam starch mucilage binders, was related to their surface tension and viscosity. The dissolution test used the basket at 50 rpm and pH 5.8 phosphate buffer.
3. Thermal Stability of Thiazide and Related Diuretics During Superheated Water Chromatography
Guilan Huang, Roger M. Smith. Chromatographia 2010, 72, December (No. 11/12)
To study the thermal stability of the thiazides a set of 11 analytes (Table 1) were initially examined by conventional LC on an XBridge C18 column using a water-acetonitrile gradient (Fig. 2a). The mixture contained three dihydrothiazides, hydrochlorothiazide, hydroﬂumethiazide and cyclopenthiazide, two thiazides, chlorothiazide and benzthiazide and two N-methyl dihydrothiazides, methyclothiazide and polythiazide, and four thiazide-like sulfonamide diuretics, chlorthalidone, clopamide, clorexolone and mefruside.