The present invention relates to a novel dry skin remedies.
The term xe2x80x9cdry skinxe2x80x9d refers to abnormal dryness of the skin over the entire body of a patient, and is used as a generic term for various symptoms caused by such a condition. The skin has various sebaceous glands and perspiratory glands and proper moisture is maintained by secretion of sebum and sweat therefrom. The abnormal skin dryness is caused by xeroderma, atopic dermatitis, and other various skin diseases; immunologic diseases such as skin allergy or Sjogren""s syndrome; metabolic diseases such as diabetes and liver disease; hormones imbalance such as postmenopausal hormones imbalance; various xerosises; administration of drugs or radiation exposure; or being placed in a dry region or dry environment; and the like. Besides the dry skin caused by such nosogenesis, there is also cryptogenic dry skin. Patients having dry skin feel dryness of the skin all over the body or topical dryness of the skin. Actual symptoms include flaring of the skin, itching (pruruitus), pain, crevice, chapped skin, or bleeding by scratching, or sclerema by chronic dry skin. These symptoms constitute severe problems in daily life.
Generally a moisturizing agent such as toilet water, creams, and lotions is used to alleviate the dryness symptoms. However, since this has a temporary effect, it must be applied often, and in some cases causes skin allergy. For curing the hormone imbalance, various hormone preparations are administered, but they have specific adverse effects. A steroid ointment can be used therapeutically as well. However, it may cause skin atrophy or fungus induction, therefore, it can only be used under limited conditions. Because of this, the treatment technique thereof has not yet been established.
In view of the above-described situation, the present inventors have extensively studied substances which promote the secretion of sweat to control the dryness of the skin and has few side effects as well as little toxicity. As a result, the inventors have found that a derivative of spirooxathiolane quinuclidine or an acid addition salt thereof, which has been known as a therapeutic agent for the treatment of diseases of the central nervous system, promotes the secretion of sweat from the perspiratory gland in the skin over the entire body. Therefore, an object of the present invention is to provide a novel therapeutic agent for the treatment of dry skin. More specifically an object of the present invention is to provide a novel therapeutic agent for the treatment of dry skin which contains a derivative of spirooxathiolane quinuclidine or an acid addition salt thereof as the active ingredient.
The present invention provides a therapeutic agent for the treatment of dry skin, containing a derivative of spirooxathiolane quinuclidine or an acid addition salt thereof, represented by the following formula (I), as an active ingredient: 
wherein, R1 and R2 may be the same or different, and each represents hydrogen, or an alkyl, cyclopentyl, cyclohexyl, aryl, diarylmethylol group or an alkyl group which is substituted by one or more aryl groups.
The term alkyl used herein refers to lower alkyl groups having 1-6 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, s-butyl, t-butyl, amyl and hexyl. The term aryl used herein refers to phenyl, tolyl, xylyl, diphenyl, diphenylmethyl, and the like.
A preferable spirooxathiolane quinuclidine derivative or an acid addition salt thereof, which is the active ingredient used in the present invention, is preferably 2-methylspiro(1,3-oxathiolane-5,3xe2x80x2)quinuclidine hydrochloride, in particular the cis-isomer.