Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: KEGG:D01453 (caffeine)
 21,611 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In a double-blind study, topically applied caffeine 30%-hydrocortisone 0.5% in hydrophilic ointment was compared to betamethasone valerate 0.1% cream and to hydrocortisone 0.5% in hydrophilic ointment. Eighty-three patients were evaluated over a three-week period for pruritus, erythema, scaling, lichenification, excoriation, oozing, and global impression. The betamethasone and caffeine-hydrocortisone groups performed significantly better than the hydrocortisone group on three of the seven scales: lichenification, excoriation, and global impression. Also, the betamethasone group differed significantly from the hydrocortisone group on six of the seven scales, but did not differ significantly from the caffeine-hydrocortisone group on any scale. It is suggested that caffeine is effective because it elevates local levels of cyclic adenosine-3',5'-monophosphate by inhibiting phosphodiesterase.
Arch Dermatol 1978 Jan
PMID:Topical use of caffeine with hydrocortisone in the treatment of atopic dermatitis. 33 46

Dopamine causes reflex erythema, central blanching, and piloerection depending on the dose and the type of application wheal reaction. Intracutaneous application shows from 1.5 gamma/0.1 ml wheal formation, erythema, piloerection, and blanching combined with increased heat radiation from the skin surface (AGA thermovision). Epicutaneous application from 500 ml (occlusive patch test) following horny layer stripping, causes marked blanching with weak piloerection. Iontophoretic application of dopamine 1/1,000 (60 s, 0.5 mA) causes only blanching and weak surrounding erythema; application of dopamine 1/100 additionally causes piloerection. This application shows no changing of infrared radiation. Iontophoretic application of dopamine 1/100 or 50 gamma/0.1 ml i.c. in a blanched area after locally applied corticosteroids (McKenzie test) shows diminution of infrared radiation proved by AGA thermovision thermography. Antihistaminics, applied externally, decrease reddening, wheal development as well as blanching by dopamine. Guanethedine (1% in eucerin) increases the blanching phenomenon (false transmitter effect of dopamine). Phentolamine 1% in W/O emulsion is without effect on dopamine reaction. Caffeine ointment (4%) reduces erythema and accentuates the degree of blanching. Oral haloperidol has no influence on the dopamine skin reaction, but increases the blanching in areas of antihistamine treatment. Skin veins and varices show marked vasoconstriction within 10 min after iontophoretic (1 : 100, 3.5 mA, 60 s) or i.c. application (50 gamma/0.2 ml).
Arch Dermatol Res 1979 Aug
PMID:Dopamine effects on the microcirculation and veins of the skin after local application and their changes by antagonistic drugs. 50 30

The distribution coefficient of caffeine (water/n-Octanol) and the estimation of caffeine in urine after local application indicate to a high permeation rate of caffeine through the skin. This could be confirmed by using different vehicles in vivo and in vitro. 14C labeled caffeine penetrates rapidly the epidermis and corium. The maximum of absorption is reached at 100 min after local application in vivo. In vitro by absence of the transport possibilities of blood and lymph vessels, the concentration at 1,000 min after local application is 450 X higher than in vivo. Therefore, after 1,000 min in vivo the concentration of caffeine in the different skin layers is very low.
Arch Dermatol Res 1979 Nov
PMID:The quantitative distribution of percutaneously applied caffeine in the human skin. 52 50

A novel transcutaneous chemical collection device (TCD) has been developed to study the phenomenon of outward transcutaneous chemical migration. The TCD is a Bandaid-like device containing an immobilized aqueous media and binding reservoir material to prevent back-transfer into the skin. This device, when placed against the skin, allows collection and quantitation of chemicals that diffuse directly through the skin from within the body. The relationship of the amount of drug collected in the TCD to the amount in the body available for collection (as represented by the area under the plasma-concentration time curve, AUC) and the effects of sweating, a potential confounding factor, on collection of drug in a TCD were studied, using caffeine as a model compound. TCD were placed on the skin of normal male volunteers. Twenty-four hours later subjects took caffeine by mouth. Blood samples were collected and TCD were removed at various times after drug intake and analyzed by HPLC for caffeine. Studies of the sweating effect were carried out in a similar manner, except that one arm of each subject was maintained at 40 degrees C to induce local sweating, the other arm acted as a non-sweating control. The amount of caffeine collected was linearly related to the AUC. Sweating seemed to have a large (40%) contribution to transdermal collection in the early period (5.5 h) of the study, but this difference was much less (14%) at longer collection times (10 h).
J Invest Dermatol 1991 Feb
PMID:Transcutaneous chemical collection of caffeine in normal subjects: relationship to area under the plasma concentration-time curve and sweat production. 199 78

Percutaneous absorption of five compounds was studied in the hairless rat in vivo: benzoic acid, caffeine, hydrocortisone, inulin and thiourea. The results clearly demonstrate that, as with in vitro experiments, a steady-state flux can be achieved in vivo. This steady-state flux is strongly molecule dependent. Thus, the values for inulin and benzoic acid differ by a factor of about 40. In contrast, although the physicochemical properties of the studied compounds vary widely, their lag times were not significantly different. The mean lag time was 11 +/- 2 min. Different compounds could be considered to have approximately the same apparent diffusion coefficient with regard to their percutaneous absorption in vivo. Thus, for a given thickness of stratum corneum and a given anatomical site, the penetration flux value of a substance depends only on its stratum corneum/vehicle partition coefficient. Using a classical model, we have demonstrated that the amount of substance present in the stratum corneum (Qsc) at equilibrium (30 min) is related to this partition coefficient. There is also a linear relationship between steady-state flux and Qsc. In practice, the in vivo steady-state flux of penetration of a compound can be predicted from the simple measurement of the amount present in the stratum corneum after a contact time of 30 min.
Arch Dermatol Res 1990
PMID:In vivo percutaneous absorption: a key role for stratum corneum/vehicle partitioning. 212 17

Cutaneous blood flow has been directly quantitated in vivo for the first time without animal death utilizing the rat skin sandwich flap. This was accomplished by conducting experiments that made a direct correlation between two instruments: a laser Doppler velocimeter and an electromagnetic blood flow meter. Data demonstrate that the correlation between these two instruments is high and reproducible (r = 0.96) with a small (1.3%) coefficient of variation. Blood flow to skin in the unmanipulated state varies from 0.7 to 1.2 mls/min in an anesthetized rat. Application of the blood flow correlation to the determination of percutaneous absorption of caffeine across human skin and benzoic acid across rat skin demonstrates that assuming cutaneous blood flow is a particular value day to day in any skin type results in an apparent wide range of total compound absorbed across that skin on independent occasions. Utilizing actual blood flow measurements to calculate the amount of chemical absorbed reduces the range of variability in the total amount of chemical absorbed and provides a more accurate knowledge of events occurring during a particular time of the absorption process. Quantitation of cutaneous blood flow will be useful in physiologic and pharmacologic studies where actual cutaneous blood flow is likely to be important to the processes studied, e.g., delivery of drug to skin, metabolism within the skin, and disposition of drug to blood and skin following topical drug application.
J Invest Dermatol 1989 Mar
PMID:Cutaneous blood flow and percutaneous absorption: a quantitative analysis using a laser Doppler velocimeter and a blood flow meter. 252 87

Percutaneous absorption of 4 radiolabeled molecules was compared in the hairless rat (back) and in different anatomic sites in human (arm, abdomen, postauricular, forehead). The conditions under which these 4 compounds were administered (area treated, dose, vehicle, contact time, etc.) were similar in both species. The results showed that, in humans and rats, there exists the same rank order in total absorption: benzoic acid sodium salt less than caffeine less than benzoic acid less than acetylsalicylic acid. In both species there was a factor of 3 between the most and the least absorbed molecule. Although skin permeability varied significantly with the physicochemical nature of the compound administered, it also depended on the anatomic site involved. Independent of the molecule studied, the rank order of permeability of the sites tested in humans appeared as follows: arm less than or equal to abdomen less than postauricular less than forehead. There was a factor of 3 between the most and the least permeable sites. For each molecule and each anatomic site, the ratios of total percutaneous absorption human/hairless rat (back) were determined. For a given anatomic site and whatever the molecule tested, these ratios were constant. It thus appears that when conditions are carefully controlled, it may be possible, by measurements on animals, to predict the absorption of a compound in humans. Further experimentation with chemicals of varied physicochemical properties will be required for validation of the model.
J Invest Dermatol 1987 May
PMID:The hairless rat: a relevant animal model to predict in vivo percutaneous absorption in humans? 357 28

The percutaneous absorption of benzoic acid, caffeine and testosterone through human skin was measured by using in vivo and in vitro techniques. The compounds were applied to the skin in solution in three vehicles: petrolatum, ethylene glycol gel and water gel. Because benzoic acid was ionized at the neutral pH of the gels, these data were difficult to interpret and are not reported. The stratum corneum/vehicle partition coefficients (Km) and percent saturation of the vehicles with substrate were determined to aid in the interpretation of the absorption results. In the in vitro studies, the permeability constants determined for the compounds in each vehicle correlated with either the Km value or the percent saturation of the vehicle. Caffeine penetrated most readily from a petrolatum vehicle, and the greatest testosterone absorption was from a water gel. Permeation was also expressed in terms of the percentage of the applied dose absorbed. Reasonable agreement was obtained between the in vivo and in vitro values. Although no significant differences occurred between most values compared, there was a trend toward lower penetration in the in vitro system.
Br J Dermatol 1986 Jul
PMID:Vehicle effects on percutaneous absorption: in vivo and in vitro comparisons with human skin. 373 Feb 75

The human skin grafted congenitally athymic (nude) mouse, pig skin grafted nude mouse, hairless dog, and weanling Yorkshire pig were evaluated as models for predicting skin penetration in man. Nine radiolabelled compounds previously tested on man were applied topically (4 micrograms/cm2) to each model. These compounds included caffeine, benzoic acid, N, N-diethyl-m-toluamide, three steroids, and three insecticides. To correct for incomplete excretion of the label following topical absorption, per cent penetration was calculated by dividing the per cent of the topically applied radioactive dose recovered in the excreta by the corresponding percentage after parenteral administration and multiplication by 100. Calculated values of per cent penetration were confirmed in the case of the grafted nude mouse because significant correlations (r = 0.78 for human skin grafted athymic nude mouse and r = 0.97 for pig skin grafted athymic nude mouse) were found between the calculated values and the actual values obtained by summing the radioactivity recovered in the urine, faeces, tissues, and carcass. The results also revealed a significant correlation between human skin grafted athymic nude mouse values and human values (r = 0.74, P = 0.05) and between weanling Yorkshire pig values and human values (r = 0.83, P = 0.05). In contrast, no significant correlation existed between human values and those of the hairless dog and the pig skin grafted athymic nude mouse.
Br J Dermatol 1984 Jul
PMID:Percutaneous penetration in the hairless dog, weanling pig and grafted athymic nude mouse: evaluation of models for predicting skin penetration in man. 620 72

The effects of caffeine and coffee, agents widely alleged to provoke flushing in patients with erythematotelangiectatic rosacea, were investigated. Neither caffeine nor coffee at 22 degrees C led to flushing reactions. Both coffee at 60 degrees C and water at 60 degrees C led to flushing reactions with similar temporal characteristics and of similar intensities. It is concluded that the active agent causing flushing in coffee at 60 degrees C is heat, not caffeine.
J Invest Dermatol 1981 Jan
PMID:Oral thermal-induced flushing in erythematotelangiectatic rosacea. 645 Aug 9


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