Effect of Tetrabutylammonium Bromide-Based Deep Eutectic Solvents on the Aqueous Solubility of Indomethacin at Various Temperatures: Measurement, Modeling, and Prediction with Three-Dimensional Hansen Solubility Parameters.

Deep eutectic solvents (DESs) have recently been getting a great deal of attention in many fields of science and technology. The objective of this study was to peruse the solubility of indomethacin (IMC) as sparingly soluble drug in some tetrabutylammonium bromide (TBAB)-based DESs (TBAB/ethylene glycol and TBAB/glycerol). The shake flask method has been employed in this study at temperature ranges T = (298.15-313.15) K and atmospheric pressure (pP = 86.6 kPa). The results showed that the solubility of IMC in TBAB/ethylene glycol system was obtained approximately 17,000-fold more than its solubility in water. The solubility data were accurately correlated by the famous local composition activity coefficient models including e-NRTL and UNIQUAC. It was also our aim to evaluate Hansen solubility parameters in IMC solubility prediction. These parameters can help to predict the solvent performance during the manufacturing processes and will be useful in guessing solvent behavior in many other fields of effort. The experimental and the Hansen solubility parameters results are very well matched. In addition, the apparent thermodynamic properties of dissolution and mixing were studied in these solutions based on Van't Hoff and Gibbs equations.

Pentoxifylline: a drug with wide spectrum applications in dermatology.

Pentoxifylline (PTX) is a methylxanthine derivative with a variety of anti-inflammatory effects. Currently, PTX is approved by the Food and Drug Administration for the treatment of intermittent claudication, but studies have shown that it has a variety of physiological effects at the cellular level, which may be important in treating a diverse group of diseases.

Administración de fármacos utilizados en dermatología durante el embarazo y la lactancia (I) / Administration of drugs used in dermatology during pregnancy and breastfeeding (I)

No disponible

Dapsone and sulfapyridine.

Dapsone and sulfapyridine are structurally related compounds with anti-microbial and anti-inflammatory effects. Dapsone remains the most important drug for leprosy and is useful in the prophylaxis of Pneumocystis pneumonia in patients with HIV disease. The medical treatment of choice for dermatitis herpetiformis is dapsone; and sulfapyridine also can be used for those patients who are intolerant of dapsone. Other neutrophilic disorders also may respond to these drugs. Toxic side effects of both dapsone and sulfapyridine are mediated through the hydroxylamine metabolite. These include hemolysis, methemoglobinemia, and agranulocytosis. Careful monitoring for possible adverse reactions includes frequently performing complete blood counts and regular blood chemistry profile determinations.

Pharmacokinetic profiles in rats after intravenous, oral, or dermal administration of dapsone.

Dapsone is a potent anti-inflammatory and antibacterial agent that has been used extensively in the oral treatment of leprosy and dermatitis herpetiformis. This study compared the pharmacokinetic profile of dapsone in rats given a single oral or i.v. 12 mg/kg dose (n = 8/group) or a single dermal application of 12 or 60 mg/kg (n = 12/group) in an aqueous gel application medium containing 10 or 25% diethylene glycol monoethyl ether (DGME). Blood samples (200 microl) were collected via tail vein from each rat and pooled at intervals up to the 24-h period. A terminal blood sample was collected by cardiac puncture from each animal. Plasma concentrations of dapsone were determined by liquid chromatography atmospheric pressure ionization tandem mass spectroscopy. There was no treatment-related overt toxicity observed in any of the animals. Peak levels were reached 1 h after oral dosing (4890 ng/ml), and 6 to 8 h after dermal application, with Cmax values of 1.62, 5.56, and 12.8 ng/ml, for 12 mg/kg at 10 or 25% DGME, and for 60 mg/kg at 25% DGME, respectively. Bioavailability was calculated at 78% after oral dosing and <1% after dermal application. Apparent elimination half-lives (t(1/2))s were similar after i.v. and oral dosing. Both the calculated area under the plasma concentration versus time curve up to 24 h and Cmax values were 3- to 4-fold higher in the dermal application group administered 12 mg/kg dapsone in 25 versus 10% DGME gel, whereas the calculated area under the plasma concentration versus time curve up to 24 h and Cmax values for the 60 mg/kg group were only 3.3- and 2.3-fold greater than those obtained after application of 12 mg/kg in 25% DGME. These results show that both systemic exposure and peak plasma concentrations of dapsone are minimized by dermal versus oral administration of the compound.