A three way crossover study in 25 fasting healthy subjects was conducted to compare the bioavailability of the B 12 nasal spray to the B 12 nasal gel and to evaluate the relative bioavailability of the nasal formulations as compared to the intramuscular injection. The peak concentrations after administration of intranasal spray were reached in +/- hours. The average peak concentration of B 12 obtained after baseline correction following administration of intranasal spray was +/- pg/mL. The bioavailability of the nasal spray relative to the intramuscular injection was found to be %. The bioavailability of the B 12 nasal spray was found to be 10% less than the B 12 nasal gel. The 90% confidence intervals for the loge-transformed AUC (0-t) and Cmax was % - % and % - % respectively.
For external exposure, bathing the mucous membrane surfaces that have contacted capsaicin with oily compounds such as vegetable oil, paraffin oil , petroleum jelly ( Vaseline ), creams , or polyethylene glycol is the most effective way to attenuate the associated discomfort; [ citation needed ] since oil and capsaicin are both hydrophobic hydrocarbons the capsaicin that has not already been absorbed into tissues will be picked up into solution and easily removed. Capsaicin can also be washed off the skin using soap, shampoo, or other detergents . Plain water is ineffective at removing capsaicin,  as are bleach, sodium metabisulfite and topical antacid suspensions. [ citation needed ] Capsaicin is soluble in alcohol, which can be used to clean contaminated items.