Camphor is extremely pungent. When diffused with care, camphor can be useful as a cardiac stimulant and to open blocked respiratory passages. The aroma of camphor seems to be very effective for a particular type of nervous depression where great agitation precedes a loss of energy and stamina and a feeling of deep despair. Camphor has been used, in dilution, to stimulate circulation, metabolism, and digestion. Camphor has a reputation as anti-inflammatory and as a pain reliever. Considered by many to be too strong to use alone.