Citronellol, or dihydrogeraniol, is a natural acyclic monoterpenoid. Both enantiomers occur in nature. (+)-Citronellol, which is found in citronella oils, including Cymbopogon nardus (50%), is the more common isomer. (−)-Citronellol is found in the oils of rose (18-55%) and Pelargonium geraniums. Citronellol can be prepared by hydrogenation of geraniol or nerol.

Citronellol is used in perfumes and insect repellents, and as a mite attractant. Citronellol is a good mosquito repellent at short distances, but protection greatly lessens when the subject is slightly further from the source. When complexed with β-cyclodextrin, it has on average a 1.5 hour protection duration against mosquitoes. Citronellol is used as a raw material for the production of rose oxide.

Menthol is an organic compound made synthetically or obtained from corn mint, peppermint or other mint oils. It is a waxy, crystalline substance, clear or white in color, which is solid at room temperature and melts slightly above. Menthol has local anesthetic and counterirritant qualities, and it is widely used to relieve minor throat irritation. Menthol also acts as a weak κ-opioid receptor agonist.

Menthol's ability to chemically trigger the cold-sensitive TRPM8 receptors in the skin is responsible for the well-known cooling sensation it provokes when inhaled, eaten, or applied to the skin. In this sense, it is similar to capsaicin, the chemical responsible for the spiciness of hot chilis (which stimulates heat sensors, also without causing an actual change in temperature).

Menthol's analgesic properties are mediated through a selective activation of κ-opioid receptors. Menthol also blocks voltage-sensitive sodium channels, reducing neural activity that may stimulate muscles. A study showed that topical absorption of ibuprofen is not increased by menthol, but does note the complementary effect of the menthol as a pain reliever itself.

Menthol is widely used in dental care as a topical antibacterial agent, effective against several types of streptococci and lactobacilli.

(+)-Neomenthol is found in cabbage. (+)-Neomenthol is a constituent of Japanese peppermint oil. (+)-Neomenthol is a flavouring ingredient. (+)-Neomenthol belongs to the family of p-Menthane Monoterpenes. These are monoterpenes whose structure is based on the p-menthane backbone.

This compound belongs to the class of organic compounds known as menthane monoterpenoids. These are monoterpenoids with a structure based on the o-, m-, or p-menthane backbone. P-menthane consists of the cyclohexane ring with a methyl group and a (2-methyl)-propyl group at the 1 and 4 ring position, respectively. The o- and m- menthanes are much rarer, and presumably arise by alkyl migration of p-menthanes.