Intra-dermal injections

In addition to the flush, wheal, and flare, transient pain and itching result from the effects of histamine on sensory nerve endings. In sensitized individuals, intra-dermal injection of specific antigens produces a wheal this reaction is the basis for a skin test to quantify the extent of the allergic response. 

Peak concentrations of these drugs are achieved rapidly in the skin and persist after plasma levels have declined. This is consistent with inhibition of wheal and flare responses to the intra-dermal injection of histamine or allergen, which last for 36 hours or more after treatment, even when concentrations in plasma are very low. Such results emphasize the need for flexibihty in the interpretation of the recommended dosage schedules (Table 24-2) less frequent dosage may suffice. Doxepin, a tricyclic antidepressant (see Chapter 17), is one of the most potent antihistamines available it is -800 times more potent than diphenhydramine. This may account for the observation that topical doxepin can be effective in the treatment of chronic urticaria when other antihistamines have failed. 

Moreover, about 14 hours after the test we are no longer capable of distinguishing between the patch tests performed with the various substances we employed. However, we have observed differences in the disappearance time of the reaction. The erythema due to CA diminishes rapidly after 14 hours that due to DNCB and PNDMA diminishes quite quickly after about 24 hours that due to potassium bichromate diminishes more slowly, but in this case the test is performed by intra-dermal injection and not by epicutaneous application. On the other hand, the intensity of the test with PA continues to increase between 14 and 24 hours until the epidermis actually gives the impression of potential erosion, but this phenomenon subsides and the reaction slowly diminishes, more slowly than with DNCB. 

Vaccines Vaccinia virus is a live poxvirus that can lead to strong cross-protection to smallpox for about five years, plus partial protection for ten or more years. If your are old enough, or have been in military service in recent years, you may have been vaccinated with this vaccine administered by dermal scarification, or intra-dermal jet injection. However, certain persons should NOT receive smallpox vaccine, including persons who are pregnant, persons who underwent a clinical immunosuppresion, persons with eczema, or persons with leukemia or lymphoma. 

Primary routes of entry of toxicants to the human body are dermal, gastrointestinal, and respiratory. Methods for studying these different routes are numerous, but they are perhaps best developed for the study of dermal absorption because this route is subject to more direct methodology, whereas methods for studying respiratory or gastrointestinal absorption require more highly specialized instrumentation. Additional routes encountered in experimental studies include intraperitoneal, intramuscular, and subcutaneous routes. When direct entry into the circulatory system is desired, intravenous (IV) or intra-arterial injections can be used to bypass the absorption phase. Information from this more direct route of entry (e.g., IV) should, however, be used in addition to data from the extravascular route of interest to adequately assess the true extent of absorption of a toxicant. 

A wide range of doses and immunization schedules has been used successfully. A convenient schedule for immunization of rabbits is to inject 200-500 fjLg of conjugated protein, emulsified in complete Freund s adjuvant, intradermally and subcutaneously on the first day, and to inject the same dose in incomplete adjuvant on days 14 and 21. Serum can be obtained 5-7 days later. Further bleedings may be done weekly, with intra-dermal booster injections given if the serum antibody levels fall. After an... 

This is the correct amount of medication to administer to the client intra-dermally. This is the prescribed dose when administering a PPD intradermal injection to a cKent who is being tested for possible exposure to tuberculosis. 

For the antigen injection, the experimenter has a choice among intramuscular (im), intra-dermal (id), subcutaneous (sc), intravenous (iv), or intraperitoneal (ip) injection. In bigger animals, with some anatomical knowledge, injection into the lymph nodes is also possible. The id injection requires skill, but it is said to give a better immune response. In addition, it provides for a longer depot effect. Chopped-up gel pieces cannot be injected intradermally and mouse skin is too thin for id injections. 

Fig. 1. Evaluation of quantitative PCR (qPCR) methods to quantify Yersinia pestis in host and vector tissues. (A) Comparison of qPCR and colony-forming unit (CFU) methods to track the decline in numbers of an attenuated Y. pestis strain after intra-dermal (ID) injection. Skin biopsies from individual mice were taken 0-7 days after injection with 10 Y. pestis KIM6+. Biopsies were triturated with a tissue homoge-nizer and divided equally for qPCR and plate count assays. (B) Comparison of qPCR and CFU methods to quantitate Y. pestis in infected fleas. Flea triturates (see step 4, Subheading 3.1.2.) were divided equally for qPCR and plate count assays. (C) Standard curve prepared for qPCR of Y. pestis in rat lymph nodes as described in Subheading 3.1.4.

Grimmer (1961) pointed out that if sensitization is carried out through the lymph nodes or the spleen, only a dermal reaction is obtained. Recently this has also been emphasized by Klaschka (1966). The histological picture is different according to the means of sensitization (DNCB) solely dermal lesions (sensitization by intravenous and intraperitoneal injections) or combined dermal and epidermal lesions (epicutaneous applications or intra-cutaneous injections). 

A 68-year-old man with type 2 diabetes treated with insulin and oral hypoglycemic agents developed pruritic plaques of more than 15 cm diameter at the site of his insulin injections. Skin biopsy showed an Arthus type reaction. Various insulin therapies, including insulin glargine, insulin detemir, and human insulin, produced the same response. Intra-dermal tests were positive to a variety of insulins and protamine. He was desensitized using subcutaneous human insulin and orally fexofenadine 180 mg bd and was then successfully treated with insulin glargine. The fexofenadine was stopped 6 months later. 

The development history of the first intra-dermal hyaluronan-based microimplants warrants brief review. Since the early 1980s, HA microimplant injections have been commonly and widely used for correction of depressive cosmetic defects. In 1984-1988, the preparation... 

Some of the dosage formulations available for protein pharmaceuticals are listed in Table 5.7. An examination of Table 5.7 reveals that no protein drug up until this time has been formulated for oral administration. Most protein drugs are administered by means of injection (parenteral administration). Parenteral administration includes intravenous, intra-arterial, intracardiac, intraspinal or intrathecal, intramuscular, intrasynovial, intracuta-neous or intradermal, subcutaneous injections, and injection directly into a dermal lesion (e.g., a wart). The parenteral route of administration requires a much higher standard of purity and sterility than oral administration. It also may require trained... 

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