Ukubhema kuwumkhuba lapho into ethile ishiswa khona bese intuthu eholelwa kuyo iphefumulelwa ukunambitheka nokufakwa egazini.Ngokuvamile, into esetshenziswayo amaqabunga omisiwe esitshalo sogwayi, asongwe engxenyeni encane yephepha eligingqikayo ukuze enze isilinda esincane esiyindilinga esibizwa ngokuthi " ugwayi ".Ukubhema kwenziwa ikakhulukazi njengendlela yokuphatha yokusetshenziswa kwezidakamizwa zokuzijabulisa ngoba ukuvutha kwesitshalo esomile kushiya kuphefumule futhi kuhambise izinto ezisebenzayo emaphashini lapho zingena khona ngokushesha egazini futhi zifinyelele ezicutshini zomzimba.Endabeni yokubhema ugwayi lezi zinto ziqukethwe enhlanganisweni yezinhlayiya ze-aerosol namagesi futhi kufaka ne-alkaloid nicotine esebenzayo ekhemisi; ukuphefumula kudala i-erosol evuthayo negesi ibe yifomu evumela ukuhogela kanye nokungena okujulile emaphashini lapho ukumunceka khona egazini lezinto ezisebenzayo kwenzeka.Kwamanye amasiko, ukubhema kwenziwa futhi njengengxenye yamasiko ahlukahlukene, lapho ababambiqhaza bekusebenzisa khona ukusiza ukubhebhetheka kwezimo ezifana nokuthi, bakholelwa ukuthi, kungaholela ekukhanyeni okungokomoya. Ukubhema kungenye yezindlela ezivame kakhulu zokusetshenziswa kwezidakamizwa zokuzijabulisa.Ukubhema ugwayi kuyindlela ethandwa kakhulu, eyenziwa ngabantu abangaphezu kwesigidi esisodwa emhlabeni jikelele, iningi labo emazweni asathuthuka.Izidakamizwa ezingandile kakhulu zokubhema zifaka i- cannabis ne- opium.Ezinye zezinto zihlukaniswa njengama- narcotic anzima, njenge- heroin, kepha ukusetshenziswa kwalezi zinto kunomkhawulo njengoba kuvame ukungatholakali ngokuthengisaOsikilidi bakhiqizwa ngokuyinhloko ezimbonini kodwa futhi bangasongwa ngesandla kusuka kugwayi ovulekile kanye nephepha eligingqikayo.