Prilocaine preparations

Prilocaine (4.138), a chiral local anesthetic, was hydrolyzed stereoselec-tively at its amide bond. Indeed, the plasma concentrations of the (-)-(/ )-enantiomer were lower than those of the (+)-(5 )-enantiomer after i.v. administration in the cat. In vitro studies of liver preparations from various mammals confirmed that the (R)-isomer was hydrolyzed at much higher rates than the (.S )-form [84],... 

EMLA cream (lidocaine 2.5% and prilocaine 2.5%) consists of a eutectic mixture of focal anesthetics. It is used to provide topical anesthetic to intact skin. Other topical preparations are effective only on mucosal surfaces. EMLA has been shown to reduce pain on venipuncture and provide substantial anesthesia for skin graft donor sites. No significant local or systemic toxicity has been demonstrated. 

A 5-year-old child had 35 g of Emla apphed under an occlusive dressing to eczematous skin in preparation for cryotherapy for molluscum contagiosum (3). Within 1 hour, the child had a generalized seizure that lasted 10 minutes. The plasma concentrations of lidocaine and prilocaine 30 minutes later were 5.5 and 2.0 pg/ml, respectively, and 6 hours later, the methemoglobin concentration was 19%. The child was given vitamin C 500 mg intravenously, and 2 days later had a methemoglobin concentration of 0.3%. 

Local anesthetics make use of the lipophobic property of an aromatic amine moiety, or its acyl derivative, that links with a hydrophilic amino acid. The products include the anilide lidocaine, or 2-(diethylamino)-A-(2,6-dimethylphenyl)acetamide (153), the toluidine derivative prilocaine and the century-old procaine, 2-diethylaminoethyl 4-aminobenzoate (154)84. The ester is prepared by reacting p-aminobenzoic acid with ethylene chlorohydrin and diethylamine. 

Feldene piroxicam. felodipine [ban, inn, usan] (Plendil etc.) is a dihydropyridine calcium-channel blocker with VASODILATOR properties, which can be used in ANTIHYPERTENSIVE therapy and antianginal prophylaxis, felypressin [ban, inn, usan] ([Phe Lys ]vasopressin phelypressin PLV2 Octapressin Octopressin ) is a synthetic analogue of vasopressin. It is a VASOCONSTRICTOR and is incorporated into LOCAL ANAESTHETIC preparations to prolong their duration of action. (It is a constituent with prilocaine of Citanest with Octapressin .)... 

Bromo-o-propiono toluidine may be prepared by the condensation of a mole each of o-toluidine and 2-bromopropionyl bromide with the elimination of a mole of hydrogen bromide. This on further condensation with one mole of propyl amine yields the prilocaine base which on reaction with an equimolar amount of hydrochloric acid gives the official compound. 

Are there any stereochemical requirements of local anesthetic compounds when they bind to the sodium channel receptors A number of clinically used local anesthetics do contain a chiral center (i.e., bupivacaine, etidocaine, mepivacaine, and prilocaine) (Table 16.2), but in contrast to cholinergic drugs, the effect of optical isomerism on isolated nerve preparations revealed a lack of stereospecificity. In a few cases (e.g., prilocaine, bupivacaine, and etidocaine), however, small differences in the total pharmacological profile of optical isomers have been noted when administered in vivo (41,42,43). Whether these differences result from differences in uptake, distribution, and metabolism or from direct binding to the receptor has not been determined. 

Amethocaine (tetracaine), bupivacaine, Ugnocaine (lindocaine), prilocaine, and procaine FIA Lignocaine in local anaesthetic preparation Bupivacaine and procaine 5X10" M, lignocaine 7X10- M (205)... 

A safe IV line is always necessary, and our preference goes to an antecubital catheter. The largest possible size is chosen. Placement of the catheter is ideally performed by a nurse in the outpatient suite after skin preparation with anesthetic cream (lidocaine-prilocaine, Emla ). This catheter makes it possible to use a power injector. Power injection provides an excellent examination quality, and continuous flow decreases the risk of extra vascular passage. The injection should be visually monitored and stopped in case of extra-vascular passage. In younger children, hand injection under visual control seems safer. 

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