Poison ivy

Chelated complexes such as sodium zirconium lactate [15529-67-6] or ammonium zirconium carbonate [22829-17-0] and acidic forms such as zirconium hydroxy oxide chloride [18428-88-1] have been used in preparations in deodorants or for treatment for poison oak and poison ivy dermatitis. In such occasions, when the skin had been cut or abraded, a few users developed granulomas which have been identified as a delayed hypersensitivity to zirconium (99). These may take several weeks to develop, and commonly persist for 6 months to over a year. 

Another approach to increase the heat distortion temperature is to produce cocondensates of bisphenol A with bishydroxyphenyl fluorene. Some variations of this copolymer had heat distortion temperatures in excess of 200°C and with the potential to be produced at lower cost than such temperature-resistant thermoplastics as polysulphones and polyetherimides. Plans to develop this material were however abandoned when it was found, during trials of test materials, that workers developed skin rashes said to be similar to those encountered on contact with poison ivy. 

As an allergen for testing purposes, synthetic 3-pentadecylcatechol is more useful than natural poison ivy extracts (of which it is one component). A stable crystalline solid, it is efficiently prepared in pure form from readily available starting materials. Outline a reasonable synthesis of this compound from 2,3-dimethoxybenzaldehyde and any necessary organic or inorganic reagents. 

Phenols occur widely throughout nature and also serve as intermediates in the industrial synthesis of products as diverse as adhesives and antiseptics. Phenol itself is a general disinfectant found in coal tar methyl salicylate is a flavoring agent found in oil of wintergreen and the urushiols are the allergenic constituents of poison oak and poison ivy. Note that the word phenol is the name both of the specific compound hydroxybenzene and of a class of compounds. 

Topical anesthetics temporarily inhibit the conduction of impulses from sensory nerve fibers. These drug s may be used to relieve itching and pain due to skin conditions, such as minor bums, fungus infections, insect bites, rashes, sunburn, and plant poisoning, such as poison ivy. Some are applied to mucous membranes as local anesthetics. Examples of local anesthetics include benzocaine (Lanacane), dibucadne (Nupereainal), and lidocaine (Xylocadne). 

Glycerin is used in many skin creams and medicines, such as eye and ear drops, poison ivy creams, suppositories, and contraceptive jellies. It is also used as an emollient (skin softener) in soaps. 

Irritant contact dermatitis results from first-time exposures to irritating substances such as soaps, plants, cleaning solutions, or solvents. Allergic contact dermatitis occurs after an initial sensitivity and further exposure to allergenic substances, including poison ivy, latex, and certain types of metals. 

Plant resins, poison ivy, poison oak, poison sumac Metals (nickel or gold in jewelry)... 

A 45-year-old female presents to a pharmacy with complaints of itching and wants a recommendation to treat it. Upon visual examination you see that she has erythematous papules on both legs. After further questioning, you learn that she has recently spent a great deal of time outside at a family picnic. She states that the picnic was in a wooded area near her home and that she and several others went on a short hike that day. She states that she was wearing shorts and "probably" came into contact with the grasses and weeds that lined the hiking trail. The rash appeared the same day as the picnic and she says that it seems to have spread since it first developed. From the information she has presented, you conclude that she has been exposed to poison ivy. 

Allergenic plants causing skin eruption by contact include poison ivy (Rhus radicans L.), poison oak (Rhus toxicodendron L.), poison sumac (Rhus vernix L.), and stinging nettle (Urtica dioica L.). In the United States, poison ivy and poison oak cause nearly 2 million cases of skin poisoning and skin irritation annually, for a loss of 333,000 working days. In addition, these weeds cause 3.7 million days of restricted activity among those people who are susceptible to the toxins (1). 

Poison ivy products Negate antigens, augment chemical barrier... 

The pharmacist will, from time to time, be called upon to examine an eruption or condition and make recommendation for treatment. If and only if the condition is unmistakable in origin, delimited in area, and of modest intensity should the pharmacist recommend an over-the-counter remedy for its symptomatic relief. Physicians neither need nor want to see inconsequential cuts, abrasions, or mosquito bites or unremarkable cases of chapped skin, sunburn, or poison ivy eruption, and so on. However, if infection is present and at all deep-seated or if expansive areas of the body are involved, otherwise minor problems can pose a serious threat and physician referral is mandatory. Patients should also be directed to counsel with a physician whenever the origins of a skin problem are in question. 

Cyclopropane 87, obtained from n-butyl vinyl ether, rearranges to dihydrofuran 88 only at elevated temperature, and also partly during work-up on silica gel113). The complete conversion of 87 into veratrole by the action of HCl/CH3OH gave rise to the analogous two-step synthesis of hydrourushiol monomethyl ether from l-diazo-3,3-dimethoxy-2-nonadecanone 89113). Ether cleavage of the product yields hydrourushiol, one of the vesicant components of, inter alia, poison ivy. 

CD8 Cell associated Antigen presented by MHC I clonal expansion of CD8 cells Activation of cytotoxic (CD-8) T cells Contact dermatitis (poison ivy) Chronic hypersensitivity pneumonitis... 

The most frequent causes of allergic contact dermatitis in the United States include plants (poison ivy, poison oak, and poison sumac), metallic salts, organic dyes, plastic resins, rubber additives, and germicides.74 The most common skin patch test allergens found to be positive in patients along with potential sources of exposure are shown in Table 32.1.75 In patients with occupational contact dermatitis who were skin patch tested, the common allergens included carba mix, thiuram mix, formaldehyde, epoxy resin, and nickel.76... 

The placebo effect manifests itself in many ways, revealing that a host of bodily reactions can be influenced by mental attitude and by what an individual believes should happen. One widely noted Japanese study reported monumental effects on the allergic reactions of thirteen volunteers who were highly susceptible to poison ivy. An investigator rubbed one arm of each volunteer with a harmless green leaf, which he identified as poison ivy. He touched the volunteer s other arm with an authentic leaf of poison ivy, which he said was harmless. Despite the subjects known susceptibility, only two of them showed an allergic reaction to the really poisonous leaf. All thirteen subjects, however, developed a rash where they had been rubbed with the misidentified leaf that was actually harmless. 

Other significant phenolic resin compounds include the mixture of urushiol variants, immunogenic compounds causing severe dermatitis from the Rhus spp. (poison ivy, poison oak and poison sumac). 

Poison ivy, poison oak Delayed contact sensitivity (allergic dermatitis)... 

As mentioned, zircon (ZrSiO ) has many forms, but the most used is the transparent crystal that is cut to resemble a diamond. There is even one form of zirconium used in medicine zirconium carbonate (dZrO COj HjO), which, as a lotion, can be used to treat poison ivy infections. 

Zirconium carbonate (dZrO COj HjO), when used as an additive to lotion, is an effective treatment for skin exposed to poison ivy. 

Estimates of exposure levels associated with sudden death have not been made because workers typically absorb considerable amounts of NG through the skin in addition to inhalation. Skin contact may also cause an irritant dermatitis resembling poison ivy, and, occasionally, allergic contact dermatitis has been reported. ... 

Nonprescription hydrocortisone preparations Temporary relief of itching associated with minor skin irritations, inflammation, and rashes caused by eczema, insect bites, poison ivy, poison oak, poison sumac, soaps, detergents, cosmetics, jewelry, seborrheic dermatitis, psoriasis, and external genital and anal itching. 

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