Like all general anesthetics, Forane (isoflurane) may lead to a decrease in intellectual function for 48 to 72 hours after use. It may also cause minor mood changes for up to six days after use. This drug may only be administered by a properly trained healthcare professional in a properly equipped environment. This drug should not be administered to pregnant women, as it is possible that it may harm the fetus. It is not known if this drug is safe for breastfeeding women. When recovering from the effects of the anesthesia, you may experience shivering, nausea, vomiting and temporary paralysis of the intestines.