消化系統(tǒng)藥物課件

1、消化系統(tǒng)藥物Digestive System Agents消化系統(tǒng)藥物Digestive System AgenCommon gastrointestinal symptoms Dyspepsia胃炎Peptic ulcer disease胃潰瘍Diarrhea泄瀉Constipation便秘Common gastrointestinal sympto 抗消化性潰瘍藥 消化性潰瘍主要十二指腸潰瘍、胃潰瘍，其發(fā)病系保護(hù)與攻擊因子失平衡有關(guān)。保護(hù)因素攻擊因子 抗消化性潰瘍藥 抗消化性潰瘍藥消化性潰瘍主要指發(fā)生在胃和十二指腸的慢性潰瘍，具有自然緩解和反復(fù)發(fā)作的特點(diǎn)。臨床主要癥狀：反酸、噯氣、周期性上

2、腹部疼痛。發(fā)病機(jī)制：損傷胃腸粘膜的攻擊因子增強(qiáng)或防御因子減弱所致?？瓜詽兯幭到y(tǒng)藥物課件Types of UlcersTypeDuodenal Ulcer十二指腸Gastric Ulcer胃LocationFirst part of small intestineStomachPain Upper abdomen, slightly to R of midline Often possible to point to site of pain Dull & more likely to occur when stomach is empty Relieved by food & ant

3、acids Same area but less well localized Often aggravated by food, may be associated with N & V Appetite reduction Persistent & severe symptoms Precipitated by smoking and NSAIDs吸煙，止痛藥Types of UlcersTypeDuodenal Ul胃壁細(xì)胞受體膽堿受體（M）胃泌素受體組胺受體（H2）激活受體，開放鈣通道，最后激活H+,K+-ATP酶，分泌H+到胃內(nèi)胃酸分泌前列腺素受體 前列腺素E，保護(hù)胃粘膜.胃壁細(xì)胞受

4、體膽堿受體（M）胃泌素受體組胺受體（H2）激活受體根據(jù)胃酸分泌機(jī)制：H2-受體拮抗劑H2 blockers質(zhì)子泵抑制劑proton pump inhibitors中和過量胃酸的抗酸藥antacids根據(jù)胃酸分泌機(jī)制：理想抗酸藥應(yīng)該是作用強(qiáng)、迅速、持久、不吸收、不產(chǎn)氣、不引起腹瀉或便秘，對(duì)粘膜及潰瘍面有保護(hù)收斂作用。本類藥物作用基本相同，主要區(qū)別在于吸收程度、作用快慢、持續(xù)時(shí)間和不良反應(yīng)?？顾崴?理想抗酸藥應(yīng)該是作用強(qiáng)、迅速、持久、不吸收、不產(chǎn)氣、不引起腹抗酸藥弱堿性物質(zhì)，中和胃酸，減輕對(duì)胃粘膜的刺激和腐蝕。氫氧化鎂：抗酸較強(qiáng)，較快，有輕度致瀉作用（Magnesium Hydroxide） 氫氧

5、化鋁：抗酸較強(qiáng)，緩慢，可致便秘（Aluminium hydroxide）影響四環(huán)素的吸收（形成絡(luò)合物）。碳酸氫鈉：抗酸弱，快而短暫，可吸收，產(chǎn)生CO2。用于酸中毒；堿化血及尿液；很少用于抗胃酸Sodium bicarbonate 一般不單用抗酸藥氫氧化鋁：抗酸較強(qiáng)，緩慢，可致便秘（Aluminium抗組胺藥物組胺的作用 在20世紀(jì)40年代，發(fā)現(xiàn) 涉及變態(tài)反應(yīng)，損傷和胃分泌的生理調(diào)節(jié)抗組胺藥物有效地減弱組胺的許多反應(yīng) 抗過敏疾病 (現(xiàn)在把這批抗組胺藥叫作H1受體拮抗劑)但不能拮抗胃部組胺對(duì)胃酸分泌的促進(jìn)作用抗組胺藥物組胺的作用H1受體和H2受體存在組胺受體的兩個(gè)亞型H2受體 在胃壁細(xì)胞存在 與胃

6、酸分泌有關(guān)H1受體和H2受體存在組胺受體的兩個(gè)亞型H2-receptor antagonistsFour FDA-approved:Cimetidine 西咪替丁 （Tagamet）Ranitidine 雷尼替丁 （Zantac）Famotidine 法莫替?。≒epcid）H2-receptor antagonistsFour FDTherapeutic effects:Promote the healing of gastric and duodenal ulcers (胃和十二指腸潰瘍)Gastroesophageal reflux dz GERD (反流性食道炎)Upper GI bl

7、eed GIB (上消化道出血) May be effective in stress ulcers (應(yīng)激性潰瘍) & peptic esophagitis (消化性食道炎) H2-receptor antagonists Therapeutic effects:H2-receptoH+,K+-ATPase (Proton Pump) inhibitorOmeprazole 奧美拉唑 (Prilosec) Lansoprazole 蘭索拉唑 (Prevacid) Pantoprazole 泮托拉唑 并且作用最強(qiáng)、效力長(zhǎng)久，選擇性高，副作用小質(zhì)子泵抑制劑Proton pump inhibito

8、rsH+,K+-ATPase (Proton Pump) inhTherapeutic usesGastroesophageal reflux dz GERD (反流性食道炎),有效率達(dá)7585。Peptic ulcer（消化性潰瘍）,服用16月，潰瘍愈合率達(dá)97，其它類藥物無效用4周，愈合率達(dá)90。Infection with H. pylori plus(Hp) (幽門螺桿菌感染),幽門螺旋桿菌83%88轉(zhuǎn)陰。Upper GI bleed GIB (上消化道出血)Therapeutic usesGastroesophageAgents Used in infection of Helico

9、bacter Pylori幽門螺桿菌（helicobacter pylori，HP ）為革蘭陰性厭氧菌，在胃十二指腸的粘液層與粘膜細(xì)胞之間生長(zhǎng)，可產(chǎn)生多種酶及細(xì)胞毒素，使粘膜損傷。是慢性胃炎、消化性潰瘍和胃腺癌等胃部疾患發(fā)生發(fā)展中的一個(gè)重要致病因子。Agents Used in infection of HeFDA-Approved Treatment Regimens for H.pylori InfectionOmeprazole 20mg b.i.d + Clarithromycin 500mg b.i.d + Amoxicillin 1g b.i.d for 10 daysLansop

10、razole 30mg b.i.d + Clarithromycin 500mg b.i.d + Amoxicillin 1g b.i.d for 10 daysBismuth subsalicylate 525mg q.i.d + Metronidazole 250mg q.i.d + Tetracycline 500mg q.i.d 14 days + H2 receptor antagonist 4 wksFDA-Approved Treatment Regimen電鏡下幽門螺桿菌 電鏡下幽門螺桿菌 有何副作用？有何困難？有何副作用？有何困難？Lacteol forte乳酸桿菌干燥物，抑

11、制腐敗細(xì)菌生長(zhǎng)、繁殖及防止蛋白質(zhì)發(fā)酵，減少腸內(nèi)產(chǎn)氣，促進(jìn)消化和止瀉作用。臨床應(yīng)用：消化不良、腹脹Digestives 助消化藥還有什么其他用途？Lacteol forteDigestives 助消化藥還有消化系統(tǒng)藥物課件Clinical classification of diarrheaTypeMechanismCausesOsmotic滲透性Unabsorbed soluteLactase deficit, magnesium antacid excessSecretory分泌性Increased secretion of electrolytesE. Coli infection, il

12、eal resection, thyroid cancerExudative滲出性Defective absorption, outpouring of mucus and/or bloodUlcerative colitis, Crohns disease, leukemiaMotility disorder傳導(dǎo)功能失調(diào)Decreased contact timeIrritable bowel syndrome, diabetic neuropathy見瀉止瀉？Clinical classification of diaLoperamide洛哌丁胺Loperamide洛哌丁胺可抑制腸道平滑肌

13、的收縮，減少腸蠕動(dòng)各種原因引起的非感染性急、慢性腹瀉的對(duì)癥治療Slows intestinal motility, allowing absorption of electrolytes and water through the intestineHelps relieve cramps and decrease stool frequencyFor travelers diarrhea, nonspecific acute diarrhea, or chronic diarrhea associated with inflammatory bowel diseaseSide effects

14、: dizziness, constipationLoperamide洛哌丁胺Loperamide洛哌丁胺Loperamide洛哌丁胺對(duì)于伴有腸道感染的腹瀉，必須同時(shí)應(yīng)用有效的抗生素治療。不應(yīng)用于需要避免抑制腸蠕動(dòng)的患者，尤其是腸梗阻、胃腸脹氣或便秘的患者。腹瀉患者常發(fā)生水和電解質(zhì)喪失，應(yīng)適當(dāng)補(bǔ)充水和電解質(zhì)。用藥過程中出現(xiàn)便秘或 48小時(shí)仍無效者應(yīng)停藥。Loperamide洛哌丁胺對(duì)于伴有腸道感染的腹瀉，必須LomotilAtropine sulfate 25mcg + diphenoxylate HCl 2.5mg 地芬諾酯+阿托品Dose: 2 tab tds-qds (max: 8 ta

15、b/day)LomotilAtropine sulfate 25mc乙酰膽堿acetylcholine乙酰膽堿acetylcholineDrug treatment for diarrheaKaolinAdsorbentsFor mild nonspecific acute diarrheaAdsorb 吸附everything in the GI tractNegligible systemic absorptionSide effects: constipation, bloating, fullness Others : Charcoal, SmectaDrug treatment fo

16、r diarrheaKao思密達(dá)Smecta蒙脫石散劑該藥不進(jìn)入血液循環(huán)系統(tǒng)，并連同所固定的攻擊因子隨消化道自身蠕動(dòng)排出體外不改變正常的腸蠕動(dòng)成人及兒童急、慢性腹瀉如需服用其它藥物，建議與該藥間隔一段時(shí)間思密達(dá)Smecta蒙脫石散劑便秘Constipation Causes:因素Disease tumors, hypothyroidism, diabetic neuropathyDrug narcotic analgesics, aluminium-containing antacids, amitriptylinePsychogenic depression, eating disorder

17、s (anorexia), conscious efforts to withhold stoolLifestyle low-fibre diet, inadequate intake of fluids, avoiding the urge to empty the bowel便秘Constipation Causes:因素Type of laxativesBulk-forming laxatives e.g Fybogel, fibrosine Emollient laxatives e.g Docusate sodiumLubricant laxatives e.g Mineral oi

18、lSaline laxatives e.g Fleet enemaHyper-osmotic laxatives e.g. Lactulose, GlycerinStimulant laxatives e.g Senna, Bisacodyl Type of laxativesBulk-forming Bulk-forming laxatives纖維Considered safest among all laxativesSafe for long term useWorks in 1 3 daysSufficient fluid consumption is required (usuall

19、y a glass)喝足夠水Side effects : bloatedness, abdominal discomfortBulk-forming laxatives纖維消化系統(tǒng)藥物課件Lubricant laxatives油性Mineral oil coats and softens stoolRecommended for patients who need to avoid straining (hemorrhoid surgery, childbirth).Normally short term use短暫用Can cause pneumonia if it leaks into t

20、he lungsNot recommended for the elderly, stroke victims, and those with swallowing difficultiesThey are prone to aspirate, especially while lying down or at bedtimeLubricant laxatives油性Mineral oHyper-osmotic laxativesLactulose type is a special sugar-like laxativeInduce bowel movements by drawing wa

21、ter into the bowel from surrounding body tissuesThis provides a soft stool mass and increased bowel actionOften used for long-term Hyper-osmotic laxativesLactulo乳果糖 lactulose乳果糖還具有雙糖的滲透活性，可使水、電解質(zhì)保留在腸腔而產(chǎn)生高滲效果，故又是一種滲透性瀉藥，因?yàn)闊o腸道刺激性，亦可用于治療慢性功能性便秘。 糖尿病患者慎用，對(duì)半乳糖不能耐受者不宜服用？乳果糖 lactulose乳果糖還具有雙糖的滲透活性，可使水Stimulant laxativesInduce bowel movements