Nitroglycerin transdermal

Transdermal products with semisolid matrix design include Habitrol, Nitrodisc, Nitroglycerin Transdermal, and Prostep. For example, Habitrol consists of an impermeable backing laminate with a layer of adhesive and a nonwoven pad to which a nicotine solution is applied. Multiple layers of adhesive on a release liner are then laminated on the patch. The systems come in 10-, 20-, and 30-cm2 sizes corresponding to 7, 14, and 21 mg/day, respectively, delivered over 24 hours. 

These may be operative in some cases, but the more likely explanation is hydration dermatitis, especially when the device is left in place for 5-7 days before being removed. By leaving nitroglycerin transdermal systems in place for 2 weeks, I have provoked an eczematous reaction in about 35% of normal volunteers, usually becoming evident 3-4 days after removing the device. 

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. 

Despite the limitations imposed by the physiology of the skin, several marketed controUed release transdermal dmg dehvery systems are available in the United States for example, scopolamine [51-34-3] for the treatment of motion sickness, nitroglycerin [55-63-0] for angina, estradiol [50-28-2] for the rehef of postmenopausal symptoms and osteoporosis, clonidine [4205-90-7] for the treatment of hypertension, fentanyl [437-38-7] as an analgesic, and nicotine [54-11-5] as an aid to smoking cessation. These systems are designed to dehver dmg for periods of one to seven days. 

Nitroglycerin Delivery Systems. Transderm-Nitro, Nitro-dur, and Minitran are all transdermal therapeutic systems that dehver nitroglycerin [55-63-0] mol wt 227.09, at a continuous, controlled rate through intact skin for treatment of angina (95). 

The Minitran system, by 3M Health Care, is a monolithic transdermal system that deUvers nitroglycerin at a continuous rate of 0.03 mg/(cm h) (81). The dmg flux through the skin is higher than the previous two systems thus the Minitran system is a smaller size for equivalent dosing. For example, the 0.1 mg/h dose is achieved with a 3.3 cm system rather than the 5 cm systems of Transderm-Nitro or Nitro-dur. Because the skin is rate-controlling in a monolithic system and the Minitran flux is higher than the similar monolithic Nitro-dur system flux, it appears that 3M Health Care has included an additive to increase the skin flux to 0.03 mg/(cm h). Whereas this information is not apparent in Reference 81, patent information supports the hypothesis (96). 

Each of the transdermal nitroglycerin systems is effective in treating angina pectoris when worn for 12—16 h followed by an off period. The FDA recommends the period without dmg (8—12 h) to mitigate the possibiUty of the patient acquiring a tolerance to the antianginal effects of nitrate therapy. Thus, a noncontinuous dosing schedule of nitrates is recommended even with the transdermal deflvery system (81). 

The nitrates are available in various forms (eg, sublingual, transmucosal, translingual spray, and inhalation). Some adverse reactions are a result of the metiiod of administration. For example, sublingual nitroglycerin may cause a local burning or tingling in the oral cavity. However, die patient must be aware that an absence of this effect does not indicate a decrease in the drug s potency. Contact dermatitis may occur from use of die transdermal delivery system. 

Promoting an Optimal Response to Therapy N URATES The nitrates may be administered by die sublingual (under die tongue), buccal (between the cheek and gum), oral, IV, or transdermal route Nitroglycerin may be administered by die sublingual, buccal, to peal, transdermal, oral, or IV route If die buccal form of nitroglycerin has been prescribed, die nurse instructs die patient to place die buccal tablet between die cheek and gum or between die upper lip and gum above die incisors and allow it to dissolve The nurse shows the patient how and where to place die tablet in die mouth. Absorption of sublingual and buccal forms is dependent on salivary secretion. Dry mouth decreases absorption. 

Ms. Moore is admitted with severe chest pain and a possible myocardial infarction. After tests are done, her primary health care provider prescribes transdermal nitroglycerin for her angina. Develop a teaching plan that will show Ms. Moore how and when to apply the transdermal form of nitroglycerin. 

Transdermal patches arc applied to the skin. The drug is mixed with the adhesive for the patch, and so it lies next to in readily absorb many chemicals and so uch as nitroglycerin (for heart disease),... 

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