Topical administration

Ketopregnan-21-oic Acids, the 17(3-Carboxy Androstanes, and the D-Homocorticoids. In the course of studies on the metabohsm of fluocoitolone (103) the formation of the water-soluble carboxyhc acid (105, R = H) was reported. As a free 21-hydroxyl is not necessary for antiinflammatory activity, it was concluded that the esters (105, R = alkyl) of the preceding metabohte would possess antiinflammatory activity on topical administration but would be devoid of systemic activity when hydrolysis to the free acid occurs followed by... 

Local anaesthetics are more consistently effective than other therapies, but their use is controversial. High concentrations are needed for therapeutic benefit, but this also increases the amount crossing the blood brain barrier and entering the brain producing unwanted effects. Topical administration to the airways can reduce this. 

Acyclovir is available for use orally, topically, and par-enterally (for IV use). When given IV, acyclovir can cause phlebitis, lethargy, confusion, tremors, skin rashes, nausea, and crystalluria Side effects when given orally include nausea, vomiting, diarrhea, headache, dizziness, and skin rashes. Topical administration causes transient burning, stinging, and pruritus. 

Trommer, H. Neubert, R.H. (2005). The examination of polysaccharides as potential antioxidative compounds for topical administration using a lipid model system. International Journal of Pharmaceutics, Vol. 298, No. 1, 0uly 2005), pp.153-163, ISSN 0378-5173. 

Tice, T. R., Rowe, C. E., and Setterstrom, J. A., Development of microencapsulated antibiotics for topical administration to wounds. Proc. Int. Symp. Control. Rel. Bioact. Mater.,... 

Once diagnosed, patients with AlA should avoid aspirin and any other NSAIDs strongly inhibiting COX-1 their education is of utmost importance. They should receive a list of contraindicated and well-tolerated analgesics (table 2). Even topical administration (intravascular or by iontophoresis) of a NSAID may cause an asthma attack and should be avoided. 

D s (1996) Prevention of photocarcinogenesis by topical administration of pure epigallocatechin gallate isolated from green tea , Nutr Cancer, 26 (3), 325-35. 

The most common means of administering drugs to the eye is by topical administration of agents capable of penetrating the cornea and targeting the appropriate tissue for either physiological or medicinal effect [159,160]. The trilaminar structure of the transparent avascular cornea has been described previously. The... 

Fig. 10 Comparison of predicted and experimental aqueous humor concentrations following topical administration of pilocarpine.

Considerations Influencing Drug Design for Topical Administration... 

Often the demand for such a complement of properties requires a hierarchical strategy in which only the broadest possible limits are satisfied by the less demanding design requirements. For example, topical administration assists in limiting toxicity while improving targeting and pharmacokinetic response. On the other hand, the requirements for effective... 

There are a number of drugs that would be of benefit for the treatment of diseases in the interior of the eye, but for which therapeutic levels cannot be achieved by topical administration [217]. Until recently the only... 

An oximine (i.e., a substituted oxime) analogue of alprenoxime was examined in an attempt to overcome the problem of low stability in aqueous solution. To this end, the methoxime analogue of alprenolol (11.74, R = Me) was prepared and evaluated [109]. Stability in solution was greatly improved at neutral pH. Topical administration to rabbits produced a decrease in intraocular pressure that had the same onset and intensity as that produced by alprenolol, but that lasted longer. Alprenolol was, indeed, formed in eye tissues as a metabolite, with the peak concentration reached 30 min after topical administration of the methoxime. 

The provision of optimal drug action from topical administration sites (such as ointments, creams, transdermal patches, ophthalmic, ear, and nasal preparations)... 

Transdermal and Topical Administration Transdermal administration is used to apply the drug on the skin surface. The drug is absorbed and transported by blood to receptors, which may be remote from the part of the skin where the transdermal patch is. The flrst pass metabohsm is circumvented. Topical administration is used to apply the drug for local effects. The typical areas for topical application are the skin, eyes, throat, nose, and vagina. 

Drugs are administered by various means from oral to intravenous to topical. The oral route is a relatively slow process where a drug must be absorbed across the GI tract and then passed through the liver and metabolized before it becomes available to bind to receptors and perform its intended function. On the other hand, intravenous application is quick but has the potential of fast systemic reaction if adverse reactions occur. In the case of topical administration, the effects of the drug are localized. 

Elidel cream consists of pimecrolimus, which is a calcineurin inhibitor that is used for eczema or psoriasis. Patients should be advised to avoid alcoholic drink during the treatment period as consumption of alcohol may lead to facial flushing and skin irritation. Side-effects associated with the topical administration of pimecrolimus include a burning sensation, pruritus, erythema and skin infections, including folliculitis and, less commonly, impetigo. 

Q51 is available as a low-potency corticosteroid for topical administration to the skin... 

Lability can be used to advantage to create drugs that are designed for topical or intravenous infusion administration. For topical administration compounds may benefit from rapid systemic clearance to overcome possible side-effects. Thus the compound is stable at its topical site of action (skin, eye etc.) but rapidly degraded by the esterases present in blood, liver and kidneys to its inactive metabolites. This approach renders the compound selective. 

Table II lists the fermentation products licensed in the U.S. for parenteral or topical administration to animals. Most of these are also used to treat human infections. As important as these are for animal health, of far greater economic importance are the antibiotics that are incorporated into animal feeds.

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