- Codein lachat chu van tren receptor cua opioid yeu hen morphin Trong co
4. THUOC DOl KHANG DdN THUAN TREN RECEPTOR OPIOID
C6 2 chat d6i khang tren receptor opioid di~n hinh la naloxon va
naltrexon. Ca hai chat deu la d~n xuat cua morphin, c6 tac dung d6i khang don
thuan tren receptor opioid, it anh hudng toi cac receptor khac va h~u nhu
khong c6 tinh chu van, tru khi dung lieu rfft cao. 4.1. Naloxon
Duac dt)ng hoc
Naloxon bi mat hoat tinh khi dung duong u6ng nen chu yeu dung duong tiern. Thu6c phan b6 nhanh vao cac mo va dich co th~. Chuyen h6a chu yeu d
gan bang each lien hop vdi acid glucuronic, duy tri tac dung 1- 4 gid. Thoi gian ban thai 60 - 90 phut d nguoi binh thuong va keo dai d tre so sinh (3 gio). Thai tru chu yeuqua nude ti~u, khoang 50% thai trong vong 24 gid d~u.
Tac dung
Lieu thap, naloxon c6 tac dung d6i khang tren receptor 11,lieu cao tac d\lng len ca cac receptor khac. D6i khang lam mfft cac tac d\lng uc che ho hffp, uc che tim m~ch, co thiit phe quan va cac tac d\lng khac cua opioid.
Lieu dieu tri, naloxon h~u nhu khong c6 tac d\lng tren ngudi khong dung opioid, cond lieu cao gffp 10 l~n chi c6 tac d\lng giam dau, gay ngu nh~, khong uc che ho hffp, khong gay r6i lo~n tu~n hoan, tieu h6a, khong co d6ng tit va khong gay nghi~n.
Chi dinh
- Giai dQckhi qua lieu opioid hol)c dieu tri tinh tr~ng uc che ho hffp do cac opioid.
- ChAn doan xac dinh nghi~n opioid va dieu tri nghi~n opioid.
Tac dung khong mong muon
Do lam giam dQt ngQt n6ng dQcua cac opioid trong cd th~ nen c6 th~ d~n Wi hQi chung cai thu6c nhu: bu6n non, non mita, toat m6 hoi, tang huyet ap, tang nhip tim, run, co gi~t...
Che'phlim va lieu dung
Ngudi IOn:0,4 - 2mg/ 24h. Tre em: O,Olmg/kg/ 24h.
Ong tiem 0,4mg/ mL cho nglidi IOnva 6ng 0,04mg/ mL cho tre em. 4.2. Naltrexon
Naltrexon la thuQCd6i khang dl)c hi~u tren th\l th~ opiat tudng tl,t naloxon, nhllng tac d\lllg m~ hdn naloxon 2- 9 l~ va thdi gian tac d\lllg dai hdn.
Naltrexon hffp thu va khong bi mfft ho~t tinh khi dung qua dudng tieu h6a. Sau khi u6ng 1- 2 gid d~t tac d\lng t6i da, duy tri tac d\lng 24 gid.
Thu6c thudng dung cung co'cai nghi~n sau khi da ngling opioid it nhfft tu 7- 10 ngay d~ tranh hQichung cai thu6c nl)ng.