What is the difference between using sodium alginate and alginic acid in a powder formula for reflux in small children consisting of 100 g alginic acid, 5 g magnesium trisilicate, 34 g sodium bicarbonate, 1 g Aerosil, 20 g aluminum hydroxide, and 40 g mannitol, and can alginic acid be replaced by another substance with similar properties?

For the preparation of Erythromycin hydrophilic gel, can HPC 400, which is out of stock, be replaced with HPMC 4000?

Is a dose adjustment necessary when substituting dexamfetamine sulfate with amfetamine sulfate?

What could be the cause of the darker yellow color observed during the preparation of ibuprofen gel 5% (consisting of ibuprofen, hydroxyethylcellulose, benzyl alcohol, isopropanol, and sodium hydroxide), given that the hydroxyethylcellulose (HEC) raw material appeared as yellowish-white as the previous batch?

Can miconazole nitrate be used in an ear drop?

How can Bacicoline ear drops be correctly formulated for use in the middle ear, given that the current formula containing 100,000 I.E. polymyxin B, 2,500 I.E. bacitracin, 50 mg hydrocortisone acetate, a pH 6.8 boric acid/borax buffer (1.8 g boric acid and 0.13 g borax per 100 ml), 1 ml propylene glycol, and water up to 5 ml is unsuitable because propylene glycol is ototoxic and hydrocortisone acetate creates a suspension, while the middle ear requires a sterile, isotonic solution free of propylene glycol?

Which natural emulsifier is suitable for a cream containing more than 10% salicylic acid as an active ingredient, given that the formulation should only include natural components such as Lame creme, almond oil, lanolin, and sandalwood hydrosol (pH 5.9-6.0), and be preserved with benzyl alcohol, glycerin, benzoic acid, and sorbic acid?