A number of dosage forms are common and include solutions, suspensions and gels. Nasal solutions are solutions prepared for nasal administration either as drops or sprays. Nasal suspensions are liquid preparations containing insoluble materials for nasal administration, primarily as drops. Nasal gels are semisolid preparations prepared for nasal application and can be for either local or systemic use, in a water soluble or water miscible vehicle. 1 Similar results have been reported in other studies.
Some drugs are sufficiently volatile they can be carried into the nose through an inhaler.
In addition to the active drugs, nasal preparations contain a number of excipients, including vehicles, buffers, preservatives, tonicity adjusting agents, gelling agents and possibly antioxidants. Important in the formulation process is the use of ingredients that are nonirritating and compatible with the nose as discussed within each category. In general, the same excipients used in ophthalmic formulations can also be used in nasal formulations. Add sufficient Sterile Water for Injection to volume and mix well. Determine the pH, clarity and other quality control factors from a sample of the solution.