Question
Posted on: March 6 2013How to prepare: nitroglycerin 1% (g/V) Alcoholic solution 30 ml Lactose 5 gr Paraffin Wax VLB 10 gr White Vaseline AD 100 gr
Also adding tween 80 or emulsify 83 cannot handle this amount of alcohol. We finally delivered the preparation (because of urgent) in Eucerine and with extra 3% tween 80. Then the preparation still only partially succeeds because a part of the alcohol evaporates. We think that the preparation is feasible as follows: Lactose 10 or 15 grams take. Let the alcohol evaporate by rubbing out. Supplement the loss of the alcohol with VB. Petroleum jelly.
Answer
Adding Tween 80 was obviously not the correct choice. Well adding Arlacel 83, which is a W/O emulsifier, which could emulsify the alcohol in the ointment base. Alcohol, however, is a liquid that is very difficult to process in a W/O emulsion, even after diluting with water. Alcohol makes a W/O emulsion unstable! So it is wise to let the alcohol evaporate and fix the nitroglycerin on a carrier such as lactose powder. Whether the evaporate alcohol should be replaced exclusively by petroleum jelly I leave in the middle. One could divide the +/-27 grams over paraffin vlb and petroleum jelly, in the proportion that the two products are prescribed. The fact that the nitroglycerin is present undissolved in the ointment, the stability of the pharmacon is too good.