INDEX transdermal

Passive transdermal dehvery systems on the market tend to be either matrix or membrane controUed. In matrix devices, the stmctural and molecular characteristics of the dmg-polymer matrix determine dmg release. Examples of polymer matrix-controUed diffusional systems for angina prophylaxis include Nitro-Dur and Nitrodisc, which provide transdermal dehvery of nitroglycerin [55-63-0], and Erandol, a tape that releases isosorbide dinitrate [87-33-2]. Matrix diffusional systems have been used for dehvering dmgs with a wide therapeutic index. 

Nasta et al. also tried to investigate the relationship between cholesterol and mood states in the initial puerperal period. Their results showed that reduced plasma cholesterol concentration was associated with major feelings of fatigue and depressed mood [79]. In addition, West et al. compared the effects of transdermal versus oral estrogens on the vascular resistance index, mean arterial pressure, serum lipid concentrations, norepinephrine, and left ventricular structure in 10 postmenopausal women. The results showed that oral and transdermal estrogen significantly decreased the vascular resistance index, mean arterial pressure, norepinephrine, and total and low-density lipoprotein cholesterol to a similar extent [80],... 

SCOPOLAMINE [Merck Index ii 8361 12 8550] [7 ) (iot.2-P.4P>5tt,7p)]-a-(hydrox7raethyI)benzeneacetic acid 9-methyl-3-oxa-9-azatricyclo-[3.3.i.o ]non 7 yl ester hyoscine Scopo-derm TTS Transderm-V Scopolamin Hyoscin hyoscine... 

Fig. 12.22 Relationship between skin penetration and transdermal delivery of vitK at 12 h post-applieation using different fcnmulations. a Relationship between vitK eoneentration in the stratum eomeum (SC) and epidermis without SC + dermis ( E + D]). b Relationship between vitK eoneentration in the reeepUn phase (an index of transdermal delivery) and total skin (an index of skin penetration). The number of repheates is 6—8 per experimental group. (Taken from [17])...

When active substances are encapsulated in drug delivery systems, their bioavailability and therapeutic index can be improved over an extended period of time. A drug delivery system including polymer microspheres has been developed for injection, implants, transdermal patches, and aerosols (34). 

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