Rabin rabi na kwayoyi daban daban ya bambanta yadu.
Babu magani da ke cikin tsarinka har abada. A cikin maganin maganin ƙwayoyi, lokacin da ake amfani da miyagun ƙwayoyi don rage yawan raunin plasma (jini) ana kiran shi rabin rabi (t 1/2 ). (Bayyana cewa muna magana ne game da rabi-rabi na rayuwa shine mahimmanci saboda rabin rabi wani batu ne wanda ba ƙayyadadden magani ba. Alal misali, a cikin ilimin kimiyyar nukiliya, rabin rabi yana nufin lalacewar rediyo.)
Mafi yawanci, nazarin rabin rabi yana nuna ma'auni na pharmacokinetics. Pharmacokinetics yana nufin binciken yadda kwayoyi ke motsa jiki - shigarwa, rarraba da kawarwa. Dukansu magunguna da likitoci sun damu da rabin rabi a matsayin ma'auni. Duk da haka, kamar yadda aka sanar da masu amfani, yana da kyau ga kowa ya san kadan game da rabi.
Half-Life Formula
A nan ne tsari don rabin rai:
t 1/2 = [(0.693) (Volume of Distribution)] / Haɓakawa
Kamar yadda wannan ya nuna, yawan rabi na miyagun ƙwayoyi yana dogara ne da girman girmansa ko yadda yaduwar magani ke yada cikin jiki. A wasu kalmomi, yawancin miyagun ƙwayoyi ke rarraba a jikinka, ya fi tsawon rai. Bugu da ƙari, wannan rabi mai rai na miyagun ƙwayoyi yana dogara ne da ƙin yarda daga jikinka. Wannan yana nufin cewa lokacin da ƙwayar miyagun ƙwayoyi daga jikinka ya fi girma, to, rabin rabi ya fi guntu.
Bayanin kulawa, kodayenku da hanta sun kori kwayoyi.
Misalan Half-Life
Ga wasu kwayoyi masu magunguna da rayukansu:
- Oxycodone (magani mai zafi): 2 zuwa 3 hours
- Zoloft (antidepressant): 26 hours
- Phenobarbital (maganin antiseizure): 53 zuwa 118 hours
- Celebrex (NSAID ko magani mai zafi): 11,2 hours
Kinetics
A matsayin ma'auni mai mahimmanci na pharmacokinetics, rabin rai yana amfani da kwayoyi tare da saitin farko. Tsarin farko na tsarin zane na nufin cewa kawar da miyagun ƙwayoyi ya dogara ne da ƙaddamar da miyagun ƙwayoyi. Tare da samfurin farko, mafi yawan miyagun ƙwayoyi an share. Yawancin kwayoyi sun bi bin ka'idojin farko.
Bugu da ƙari, ana amfani da kwayoyi tare da zane-zane marasa tsari a cikin layi. Barasa ne misalin magungunan ƙwayoyi waɗanda aka kawar da su ta hanyar zane-zane. Bayan bayanin kula, lokacin da aka hana yin amfani da miyagun ƙwayoyi ne cikakke, kamar yadda ya faru tare da overdose, kwayoyi da suka bi ka'idar farko da suka dace don canza tsarin kin zane-zane.
Shekaru
A cikin tsofaffi, yawan rabi na maganin ƙwayar lipid-soluble (mai-mai narkewa) yana ƙaruwa saboda karuwar yawan rarraba. Manya tsofaffi suna da adadi fiye da ƙananan yara. Shekaru, duk da haka, yana da sakamako mai iyakance a kan rashin lafiya da kuma yaduwar kisa. Saboda yawan ragunan kwayoyi, tsofaffi sukan buƙaci maganin ƙwayoyi fiye da ƙasa ko fiye da ƙananan yara. A wani bayanin da aka danganta, mutanen da suke da ƙananan suna da ƙimar girma na rarraba, ma.
Tare da ci gaba da ci gaba (misali BID ko sau biyu-a-day dosing), bayan kimanin hudu zuwa biyar da rabi rayuka sun ragu, magani ya kai wani wuri mai tsabta a inda adadin miyagun ƙwayoyi ya ƙare yana daidaita ta wurin adadin da aka gudanar.
Dalilin da yasa magunguna ke daukar lokaci zuwa "aiki" shi ne saboda suna buƙatar isa wannan zartarwar jihar. A wani bayanin da aka danganta, har ila yau yana ɗaukar rayuka tsakanin hudu da biyar don magani don sharewa daga tsarinka.
Bugu da ƙari, yin la'akari da hankali game da sashi a cikin tsofaffi waɗanda ke da tsawon rabi-raunin miyagun ƙwayoyi, mutane da yarda da ƙetare ya kamata kuma su dace da maganin likitocin su. Alal misali, mutum da ciwon ƙwayar cuta na ƙarshe (cike da kodan) zai iya samun illa daga digoxin, magani na zuciya, bayan mako daya na jiyya kimanin 0.25 MG a rana ko fiye.
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