Lidocaine HCL

Fig. 4 Wide angle X-ray diffraction scans of a physical blend of Eudragit ElOO with 5 and 10% lidocaine HCL compared with lidocaine HCL crystals. (From Ref 1)...

Table 4 Mechanical properties of Eudragit ElOO films containing diphenhydramine HCL (DPH) and lidocaine HCL (L-HCL)...

As an example of the effects of an amphiphilic drug on the structure of surfactant self-assemblies. Figure 1.4 shows part of the phase diagram of monoolein, water, lidocaine base and licocaine-HCl (21). As can be seen, the cubic phase (c) formed by the monoolein-water system transforms into a lamellar liquid crystalline phase on addition of lidocaine-HCl, whereas it transforms into a reversed hexagonal or reversed micellar phase on addition of the lidocaine base. Based on X-ray data, it was inferred that the cubic phase of the monoolein-water system had a slightly reversed curvature (critical packing parameter about 1.2). Thus, on addition of the... 

Figure 1.4. Phase diagrams of the sub-system lidocaine base/lidocaine-HCl/monoolein at 35 wt% water at 20"C (a) and 37°C (b) (data from ref. (21))...

For example, pilocarpine HCl, phenylephrine HCl and lidocaine HCl solutions in concentrations higher than 10 mg/mL possess such a high buffer capacity that during administration substantial pain is experienced resulting in lachrymation and wash out of the eye drop. This is due to their high therapeutic concentrations and their pKa values in the neutral or slightly acidic range. Therefore, the pH value of these eye drops should be adjusted as near as possible to 7.4. 

M. Shukr, Formulation, in vitro and in vivo evaluation of lidocaine HCl ocular inserts for topical ocular anesthesia. Arch Pharm Res, 37,882-889,2014. 

Local anesthetics or sedation are not required for the CROSS. Generally, patients feel bearable prickling and burning sensation during the procedure. If needed, a topical anesthetic cream, such as EMLA cream (eutectic mixture of 2.5% lidocaine-HCl and 2.5% prilocaine ... 

Local anesthetics are weak bases and are usually made as HCl salts which are soluble and stable in water. The pK of the compound determines when the ionized and unionized forms are equal (see Table 1 for values of pK and percentage ionization at pH 7.4). The time of onset of the block is related to diffusion of the anesthetic into the nerve fiber, which occurs only in the unionized, or non-proton-ated form. Sodium bicarbonate is often added (1 mEq(lOml) lidocaine or 0.1 mEq(lOml) ... 

As is well known, the bilayer structure of cell manbranes exhibits hydrophobic properties in the hydrocarbon part. This means that those molecules that must interact with the membrane interior must be hydrophobic. Anesthesia is brought about by the interaction between some suitable molecule and the lipid molecules in the biological membrane at the cell interface. The effect of pressure has been reported to be due to the volume change of membranes, which reverses the anesthesia effect. Local anesthetics are basically amphiphile molecules of tertiary amines, and some have colloidal properties in aqueous solution. The anesthetic power is determined by the hydrophobic part of the molecule. Surface tension measurements showed a correlation with the anesthetic power for a variety of molecules dibucane < tetracainebupivacainemepivacaine < lidocaine < procaine (aU as HCl salts). ... 

Chloroacetyl chloride Chlordiazepoxide HCl Clemizole Diazepam Lidocaine Lorazepam Mianserin Tromantidine HCl... 

The use of elution system 1 followed by elution system 2 led to the adequate separation of benzocaine and lidocaine and from all other analytes (Table 16.3). Thus, this two-dimensional system was adequate for the analysis of cocaine mixed with adulterants. Figure 16.4 shows a picture of the chromatoplate used in the two-dimensional system the analytes were isolated using the following systems modified Dragendorff (bismuth carbonate solution -i- concentrated HCl -i- potassium... 

FIGURE 16.4 Chromatoplate picture after elution with two-dimensional system and revelation with modified Dragendorff (bismuth carbonate solntion + potassium iodide -h concentrated HCl) for cocaine, lidocaine caffeine followed by revelation with diazotization reaction by using P-naphthol for benzocaine. 

Figure 6.3 Release profiles for (a) indomethacin and (b) lidocaine in 0.05M HCl in the free state ( ) and from GlPS- ra/ -P2VP copolymer ( ). Mt is the cumulative mass released at time t, and Mgq is the mass released at equilibrium. (Reprinted from Polymer, 49, G.N. Njikang, M. Gauthier and J. Li, Sustained release properties of arborescent polystyrene-grq/it-poly (2-vinylpyridine) copolymers, 5474-5481, 2008, with permission from Elsevier.)...

---