- Codein lachat chu van tren receptor cua opioid yeu hen morphin Trong co
THUOC KICH THICH THAN KINH TRUNG LIaNG
1.D~CU'dNG
1.1.D~c di~mchung
Cac thuoc trong nhom dgu co tac dung kich thich than kinhtrung uong, kich thich trung tam ho hap, van mach lam h6i phuc cac trung tam khi bi suy ye'u.
Hftu het cac thuoc khong anh hudng true tie'p tren h~ tim mach ma thong qua co che h~ than kinh giao cam, kich thich lam tang nhip tim, tang muc tieu thu oxy cua co tim.
Tac dung cua cac thuoc thuong ngan, nen duoc si'i dung chu yeu cho cac truong hop suy ho hap va tuan hoan cap dth~ vita va nhe,
Lieu cao tat ca cac thuoc kich thich thftn kinh trung uong dgu co th~ gay co giat, tuy nhien rmrc dQva each thuc gay co gi~t co th~ khac nhau.
1.2.Ph an loai
Dua vao vi tri tac dung, thuoc kich thich than kinh trung udng dUQcchia thanh 3 nhom:
- Thuoc tac d\lng UU tien tren vo nao, lam tang ho~t dQng tl;l nhien, giam m~t moi, t~o cam giac khoan khoai: cafein, amphetamin, pipradrol...
- Thuoc tac d\lng UUtien tren hanh nao, tac d\lIlg tren trung tam ho hap va tuftn hoan tn;tc tiep hollicgian tiep qua phiin x~: niketamid, pentylentetrazol, camphora, lobelin, bemegrid ...
- Thuoc tac d\lng UUtien tren tuy song, lam tang ph an x~ tuy: strychnin.
ST,tphan chia nay chi dT,tavao tcic d1:lngch9n 19Cdlieu di€u trt. Khi dung lieu cao cac thuoc nay cothe'tcic d1:lngtren toan bi) ~ thong thdn kinh.
2.THUOC TAc Dl}NG U'U TIEN TREN VO NAO Cafein
Cafein, theophylin va theobromin la ba chat thuoc d~n xuat xanthin duoc chiet tit ca phe, che, ca cao hoac t5ng hop tit acid uric. Trong d~n xuat xanthin, cafein Ia c6 tac dung r6 tren than kinh trung uong, hai chat con lai c6 tac dung yeu, kh6ng trinh bay d phan nay.
Duac di)ng hoc
Thu6c hap thu nhanh qua duong uong va duong tiem, sinh kha dung qua duong u6ng dat tren 90%. Dat n6ng dQt6i da trong huyettuong sau khi u6ng thuoc khoang 1 gio. Thu6c phan b6 rQng rai trong co th~, qua nhau thai va sua me, th~ tich phan b60,4- 0,6L1kg. Chuyen h6a dgan bang phan ung demethyl va oxy h6a. Thai trit qua nude ti~u chu yeu dang da chuyen h6a. Thoi gian ban thai khoang 3- 7 gic, keo dai hondtre so sinh va tre de non.
Tac dung
- Tren than kinh trung uong: cafein kich thich uu tien tren vo nao lam giam cac cam giac m~t moi, bu6n ngu. Lam tang hung phan vo nao, tang nh~n cam cua cac giac quan do d6 tang kha nang lam vi~c va lam vi~c minh m~n hdn. Tuy nhien, neu dung cafein lien t\1Cva keo dai thi sau giai dOliln hung phan la uc che. Ligu cao, cafein tac d\1ng tren toan bQh~ thftn kinh gay cdn gi~t rung.
- Tren h~ tuftn hoan: cafein kich thich lam tim d~p nhanh, mlilnh,tang luu luqng tim va luu luqng mlilchvanh nhung tac d\1ngkem theophylin. a ligu digu tri, thu6c it anh hUdngWi huyet ap.
- Tren h~ h6 hap: kich thich trung tam h6 hap, lam gian phe quan va gian mlilchph5i. Tac d\1ngnay cang r6 khi trung tam h6 hap bi uc che.
- Tren h~ tieu h6a: thu6c lam giam nhu dQng rUQt,gay tao b6n, tang tiet dich vi (c6th~ gay loet dlilday- ta trang).
- Tren cd trdn: thu6c c6 tac d\1nggian cd trdn mlilchmau, mlilchvanh, cd trdn phe quan va cd trdn tieu h6a. D~c bi~t, tac d\1nggian cd trdn cang r6 khi cd trdn d trlilngthai bi co thl1t.
- Tren th~n: thu6c lam gian mlilchth~n, tang suc IQccftu th~n, giam tai hap thu Na+ nen c6 tac d\1ng lqi ti~u. Tuy nhien, tac d\1ng lqi ti~u cua cafein kem theophylin va theobromin.
- Tac d\1ngkhac: tang hOliltdQngcua cd van, tang chuy~n h6a.
Cd che: d~n chat xanthin ngan can ph an huy AMPv do uc che Clilnhtranh vai phosphodiesterase. N6ng dQAMPv tang se thuc dl1ycac phan ung lam tang calci nQi bao, tang hOliltdQngcd van, cd tim, tang chuy~n h6a, tang phan huy lipid, tang glucose mau (Sdd6 3.1).
Catecholamin Xanthin
t t
Adenylcyclase Phosphodiesterase
t t
ATP 3',5' AMPv 5'AMP
Glycogen Lipid Ca" tang
t t t
Glucose 1 phosphat Acid beo til do Tang hoat d¢ngCO
tim, co van
sedo 3.1.Co che tac dunq cua dlm chat xanthin
Chi dinh.
Kich thich than kinh trung uong khi met moi, suy nhuoc. Suy ho hap, tuan hoan.
Chi dinh khac: hen phe quan, suy tim trai cap, lei ti~u (hien nay it dung).
Chfing chi dinh
Mftn cam vdi thuoc.
Suy mach vanh, nh6i mau co tim. Nhip tim nhanh, ngoai tam thu.
cn«phiim va lieudung
Ong tiem 1mL dung dich 0,7%.
Uong 0,1- 0,2g/ lan, 2 lftnl 24h. Tiem dudi da 0,25g/ lftn, 1-2 lftnl 24h.
3. THUnC xtcn THicH UlJTIEN TREN HANH NAO
3.1. Niketamid
La thuoc tang hop, la diethylamid cua acid nicotinic. Thuoc hap thu qua
duong uong va tiem.
Tcic dung
Thuoc kich thich true tie'p va gian tie'p qua ph an xa xoang canh len trung tam ho hap va tuan hoan dhanh nao lam tang nhip, tang bien dQho hap, tang nhay cam cua trung tam ho hap vdi CO2• Tang nhip tim, tang sire co bop cua tim va tang nhe huyet ap. Thuoc khong co tac dung true tie'p tren h~ tim m~ch.
Lieu cao, thuoc tac dung tren toan b9 h~ than kinh trung uong co th~ gay co giat.
Chi djnh
Suy tuan hoan va suy h6 hap vira va nhe.
Ttic dung khong mong muon
Lieu cao co th~ gay con co giat.
Chong chi dinh
Mftn cam vdi thuoc,
Nguoi co tien sit d9ng kinh. Tang huyet ap,
Che'ph6m va lieu dung
Coramin, Cordiamin, dung dich 25%1Q15mLdung d~uong, 6ng tiem 1mL. Uong: 10- 20 giot/ Ian, ngay 2- 3 Mn.
Tiem dudi da, tiem blip 1 6ng/ l~n, 1- 3 l~n/ 24h. 3.2. Pentylentetrazol
Tcicd,!-ng
Kich thich trung tam h6 hap va tuan hoan d hanh nao, Thu6c co tac dung r6 khi cac trung tam h6 hap va tuan hoan bi uc che lam tho nhanh, thd sau, tang hoat d9ng cua tim, tang huyet ap. Kh6ng tac dung true tiep tren tim mach. Lieu cao, gay co giat.
Chi dinh.
Tro tim mach, tro h6 hap khi trung tam h6 hap va v~n m~ch bi uc che. Gay cdn co gi~t d~ digu tri b~nh tam th~n.
Ligu dung
Bi~t dtiqc:Pentetrazol, Cardiazol, Corazol.
U6ng, tiem blip: 0,1- 0,2g/ 24h.
Tiem tinh m~ch 2- 5mL dung dich 10%. 3.3. Bemegrid
La chat tang hqp, co cau truc hoa hQc ttidng tlj barbiturat nhting d6i khang voi barbiturat. Bemegrid kich thich trljc tiep trung tam h6 hap va tu~n hoan d hanh n8.o,lam tang nhip tim, tang huyet ap, tang bien d9 va t~n so' h6 hap.
Ngoai ra, bemegrid con kich thich than kinh van dQng, lam tang
d~n truyen xung dQng than kinh nen con duoc dung dieu tri chung dau day
than kinh, dau that lung. Lieu cao, thu6c gay co giat nhung mire dQ nhe
hen pentetrazol.
Chi dinh. va lieu dung
Dieu tri viem day than kinh: 0,025- 0,05g/ 24h.
Dieu tri ngQdQcbarbiturat: 0,05g/ Ian, dung nhieu l;ln trong ngay.
Chfing chi dinh.
M~n cam vdi thuoc. Tang huyet ap. DQngkinh.
Khong phoi hop vdi glycosid tim, reserpin. 3.4. Camphora
Camphora co tac dung kich thich trung tam ho hap va van mach dhanh nao, lam tang sue co bop cua tim, tang huyet ap, Ngoai ra, thu6c con co tac dung gian mach da va giam dau. Thu6c duoc dung d~ kich thich ho hap, tuan hoan khi bi suy yeuva dung ngoai d~ giam dau.
4. THUOC TAc DlJNG truTIEN TREN TUY SONG
Strychnin
Tac dung vacache'
La alcaloid cua hat rna tien.
Thu6c co tac dung uu tien tren tuy s6ng. Kich thich phan x~ tuy, tang d~n truyen th;ln kinh- Cd,tang dinh duBng va ho~t dQngcd nen thudng dung dieu tri cac trudng hQpte li~t, suy nhuQc, dai d;lm, li~t dudng.
Thu6c gay kich thich tieu hoa, tang tiet dich vi, tang nhu dQngrUQt,giup an ngon d~ tieu.
Thu6c lam tang nh~y cam cua cac cd quan cam giac: do kich thich vao trung tam nghe, nhin, ngl:ii.
Lieu cao kich thich ca vo nao, h~mh nao. Lam tang bien dQva t;ln so' ho hap, tang tU;ln hoan khi cac trung tam nay bi uc che. Lieu dQC,kich thich m~nh tuy s6ng lam tang phan x~ va gay cdn co gi?t gi6ng nhu co gi?t do u6n van. Cdn co gi?t do strychnin co tinh chat phan x~, chi xuat hi~n khi co kich thich tu ben ngoai nhu tieng dQng, anh sang ...Vi V?y, khi bi ngQ dQcstrychnin c;ln d~ b~nh nhan vao bu6ng t6i tranh mQikich thich va dung cac thu6c uc che cdn co gi?t nhu ether, thu6c ngii ...
Co che: strychnin tac dung chon IQC va d5i khang canh tranh vdi glycin tren receptor glycin d tuys5ng. Lieu cao tac dQng ca len receptor glycin dnao.
Chi dinh.
Dieu tri nhuoc co.
M~t moi, mdi 5m day, an kern ngon. Ye'u co that, liet duong.
Ch{j'ngchi dinh
M~n cam vdi thuoc. Tang huyet ap. DQng kinh. Viem gan.