Body surface area application

The measured height and weight, along with the body surface area, if applicable, should be readily available, along with... 

Tazarotene (Tazorac) is a synthetic retinoid that is hydrolyzed to its active metabolite, tazarotenic acid, which modulates keratinocyte proliferation and differentiation. It is available as a 0.05% or 0.1% gel and cream and is applied once daily (usually in the evening) for mild to moderate plaque psoriasis. Adverse effects are dose- and frequency related and include mild to moderate pruritus, burning, stinging, and erythema. Application of the gel to eczematous skin or to more than 20% of body surface area is not recommended because this may lead to extensive systemic absorption. Tazarotene is often used with topical corticosteroids to decrease local adverse effects and increase efficacy. 

In the United States, tazarotene has been approved for topical treatment of psoriasis (involving up to 20% body surface area) and mild to moderate facial acne. Application site burning, stinging, and desquamation are common side effects, especially with acne. Tazarotene is contraindicated in women who are pregnant. 

Treatment of psoriasis should be limited to once-daily application not to exceed 20% of total body surface area. Adverse local effects include a burning or stinging sensation (sensory irritation) and peeling, erythema, and localized edema of the skin (irritant dermatitis). Potentiation of photosensitizing medication may occur, and patients should be cautioned to minimize sunlight exposure and to use sunscreens and protective clothing. 

Since the late seventies, the clinical application of cisplatin has increased enormously16-18), mainly as a result of improved administration procedures and its use in combination therapy, i.e. the simultaneous application of a variety of synergistic antitumor drugs. Nowadays, usually a dosage per patient of about 100 mg of cisplatin per m2 body surface area, dissolved in saline, is given intravenously every month by standard administration protocols. 

The major risk resulting from topical treatment of psoriasis with salicylic acid is the potential chronic or acute systemic intoxication with the symptoms of burning of oral mucosa, frontal headache, CNS symptoms, pH deviation (metabolic acidosis), tinnitus, nausea, vomiting, and gastric symptoms.28-30 These symptoms may occur in topical treatment of large body surfaces, especially in children.31-33 Even lethal cases have been reported.34,35 Therefore, a concentration higher than 10%, and an application on larger surfaces especially in children are not suitable. Salicylic acid should not be applied to more than 20% of the body surface area.13 It should be noted that some topical treatments of psoriasis such as calcipotriol are inactivated by salicylic acid.36... 

Before administration of the test substance, selected healthy, young adult animals are acclimated to laboratory conditions for at least 5 days. Before the test, animals are randomized and assigned to treating groups. Approximately 24 hours before the test, the fur on the skin should be clipped or shaved from the dorsal area of the trunk of the test animal. Care must be taken to avoid abrading the skin, which could alter the permeability of the test chemical through the skin. Approximately 10% of the body surface area should be prepared for application of the test chemical. 

First, if the compound was cleared mainly by hepatic metabolism in the animal species tested and if human hepatocytes in vitro suggest the same will be true in humans, then the measured hepatocyte clearance may be used in a process called in vitro/in vivo scaling (20, pp. 207-228) to provide an estimate of the human intrinsic clearance. The application of Equation 5 then gives an estimate of the human systemic clearance. Second, the animal PK parameters of CL and Vj can be subjected to allometric scaling (20, pp. 207-228) whereby the PK parameter is related to a measurable allometric variable such as body mass, body surface area, heart rate, and so forth. (21) by fitting these parameter-variable pairs for several species to an empirical power equation of the form... 

Prescriber Order Entry Module (POEM ) provides a database of the most common medication orders. These orders are specific to drug, route of administration, formulation, age, indication/use, and weight or body surface area, if applicable. This enables more accurate and efficient point-of-care computerized order entry applications to prevent errors at the prescribing stage of drug delivery. 

A patient did die, however,after a phenol solution with a concentration of 2.3% was applied under an occlusive dressing on one-third of the body surface area and on flesh burnt by kerosene. This death led the authors to study the metabolism of phenol by applying 1 g of phenol to 75% of the body surface area in a first group of human guinea pigs . Three other groups were given total doses of up to 4 g on the same body surface area (75%). A rest period of 90 minutes was left between successive applications of 1 g. 

Preparation of skin Approximately twenty-four hours before testing, fur from the back of animals should be clipped so that no less than 10% (about 240 cm ) of the total body surface area is available for application of material. 

An alternative method is the prospective approach, which uses patient information, such as serum creatinine, patient s age, weight, height, or body surface area to empirically estimate V, K, and creatinine clearance (Cl ). Adjustments to a maintenance dose are achieved through various approaches. The most significant application of either the retrospective or prospective approach is with regard to dosing adjustment in renal failure. ... 

Notes Equations are applicable for the following conditions 37°C, ambient pressure, saturated with water vapor. MBC = maximum breathing capacity, L/min A = body surface area, sq m V = pulmonary ventilation, L/min m = mass, kg VC = vital capacity, L 71 = height, cm A = age, years. Weight of infants in ounces. Age correction for vital capacity 46-55 years = -4% 56-65 years = -8% 66-75 years = -16% over 75 years = -30%. 

Children and particularly babies have a large relative body surface area. Premature babies also have a thinner skin than adults, and lack the outer skin layer known as the homy layer or stratum comeum. In a young child with eczema, the skin may also be more damaged than in an adult with eczema. Therefore, the skin functions less well as barrier. Furthermore, application of any creams or ointments under a nappy or diaper prevents trans-epidermal water loss and leads to an increased absorption of the active substance. 

For practical reasons, the application of the adsorption method to the study of surface area and porosity has to be limited to bodies which are either very finely divided or possess an extensive pore system. It is helpful to consider the case of finely divided bodies first. 

Body-aid (i.e., the filter-aid) and precoating are often mentioned in connection with pressure filtration and the difference in their application is (1) Body aid is used when the slurry is low in solids content with fine and slimy particles that are difficult to filter. To enhance filtration coarse solids with large surface area are added to the slurry and serve as a body-aid that captures and traps in its interstices... 

Muscle tremors and convulsions are characteristic effects of acute dermal phenol toxicity in laboratory animals. Tremors that developed into convulsions and prostration were reported in rats exposed to 107.1 mg/kg liquid phenol application surface areas were not reported (Conning and Hayes 1970). In pigs, application of 500 mg/kg over 35-40% of the body surface (0.44 mg/cm2/kg) resulted in muscular tremors in the head region within 3-5 minutes of exposure (Pullin et al. 1978). This was followed by dilation of the pupils, loss of coordination, and excess salivation and nasal discharge within 5 minutes of exposure. It was followed by convulsions, coma, and death 5-7 minutes after exposure in two of three pigs. Direct application of a dose of 37.5 mg/kg phenol to the inner ear resulted in a reduced threshold for auditory brainstem response (Schmidt et al. 1990). 

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