Title: Drugs Affecting the Respiratory System
1Drugs Affecting the Respiratory System
- By
- Caiying Ye
- Department of Pharmacology, School of Basic
Medicine, Peking Union Medical College
2Introduction
- Antiasthmatics ???
- Antitussives ???
- Expectorants ???
3??
- ?????????????????,?? ??????????
- ????????,?????????
- ?????????,?????.
- ???????????????,?????,????,????????????
4??? Antiasthmatic Drugs
5Aasthma
- A chronic inflammatory disease of the airways
- Clinical feature bronchospasm, bronchial
obstruction, dyspnea - Pathologic changeslymphocyte infiltration,
mucosal oedema, vascular leakage, airway smooth
muscle proliferation. - Cellular infiltration invovling mast cell and
eosinophil triggers bronchial inflammation and
allergic response in susceptible population. - Treatment principleinhibit airway inflammation
and inflammatory mediators.
6Classifications
- ß2 adrenoceptor agonists
- Methylxanthinesaminophiline ???
- Muscarinic antagonists ipratropium bromide?????
- Glucocorticosteroids beclomethasone
dipropionate?????? - Mast cell stablizers sodium cromoglicate????
7Effect of antiathmatic drugs on intracellular
levels of cAMP
81. Adrenoceptor agonists
Nonselective Epinephrine ????(Adrenalin) Ephedirine ??? Isoprenaline ??????
ß2 agonist Salbutamol ????(albuterol ???) Terbutaline ????(Breathair) Clenbuterol ???? Formoterol ???? Bambuterol ????
91. Adrenoceptor agonists
- ????
- Activate ß2 receptor
- activate adenylyl cyclase cAMP
- Ca2 relax airway smooth muscle
- Activate a receptor
- cause vasoconstriction reduce
edema - improve airflow
- dilate the bronchus to relieve bronchospasm
- Activate ß receptor on the membrane of mast cell
inhibit release of allergic mediators
prevent allergic asthma attack
10- ????
- ????????,?????????????ß 2??????,????,??????,?????
- ?????????????,???????????????
11- ???? adrenaline,epinephrine
- ?????????
- Stimulate a, ß1 ß 2 receptors
- ß???????
- a????????????,????,???????
- ????ß1??,??????.
- ???a?????,?????????,??????.
- ????,??????,???????
12- ???ephedrine
- ???????,?????,????,??,??4-6??
- ???????????,?????
-
- ??????isoprenaline (???)
- ??????( Stimulate both ß1 ß 2 receptors )
- ????,1 min??????,??1-2 hr
- ?????????,?????
13????salbutamol(???)
- ??
- ?ß 2??????ß1??,???????
- ???????????,????
- ???????????????????????????????
142. theophylline ??? aminophylline
???cholinophylline
- Pharmacologic effects
- Relaxes airway smooth muscle
- Improves respiratory function
- Positive inotropic effect
15- Mechanism of relaxing airway smooth muscle
- ? Inhibits phosphodiesterases,leading to
intracellular accumulation of cAMP and smooth
muscle relaxation. - ?Stimulates endogenous epinephrine noradrenalin
release, relaxing airway smooth muscle. - ?Blocks adenosine receptor, antagonizing
bronchial constriction induced by endogenous
adenosine.
16- Improves respiratory function
- enhancing diaphragmatic contraction,?????????
,???????,???????? - Positive inotropic effect???????,??????,?????????
,????????????????????,?????????
17Therapeutic uses
- Acute or chronic asthma,cardiac asthma(?????)
- Chronic obstructive pulmonary disease(????????)
- Cardiac edema renal edema (???????)
18Adverse effects
- Gastrointestinalnausea, vomiting
- Cardiovascularpalpitation (??),arrhythmias(????),
??,????????????,???????
193. Muscarinic antagonists
- ??M??()??????cGMP??,???????????,????????,?????
parasympathetic neurons
M 1 and M3 receptors
Ach
Mucus gland secretion increases Airway smooth
muscle cell contracts
20Muscarinic antagonists
- ????? ipratropium bromide
- ??
- ????????????
- ??????
- ??????????
214. Glucocorticoids
- The best established anti-inflammatory drugs for
the treatment of asthma. - Glucocorticoids produce significant
anti-inflammatory, immunodepressive and
anti-shock effect, probably by attenuating
prostaglandin and leukotriene synthesis,
preventing release of inflammatory mediators and
decreasing mucus production. - Glucocorticoids are usually reserved for patients
with severe persistent asthma. - Inhaled glucocorticoids achieves a significant
anti-inflammatory effect without causing systemic
adverse effects.
22?????? beclomethasone
- (????????)
- ?????????
- ????,???????,????
- ???,NOT for acute asthmatic attacks!
- ???????oral fungal infections(??????)?
235. Mast Cell Stabilizer
- Cromolyn Sodium ????
- (Nasalcrom,Intal)
- Ketotifen ???
- Nedocromil Sodium ?????(Tilade)
24Pharmacologic Effects and Mechanism
- ????????,????????????(inhibits chloride channels
and inhibits the release of histamine and other
autacoids from mast cells) - ???????????????? (depress the exaggerated
neuronal reflexes triggered by irritant receptors
in the airways)
25Pharmacologic Effects and Mechanism
- ??????????????(bronchial hyperreactivity)
????????????????????????,????????????????
26Therapeutic Uses
- (1) ?????,???????
- (2) ??????????
- (3) ??????
- (4) ???????????
- (5) ???????
27Adverse Effects
- (1)?????????,??????
- (2)??????,??,??,??,????
28??? Expectorants
29??? Expectorants
-
- ???(expectorants)
- ???????,?????????????,??,??????,???????????
??? - ?????
- ?????????,?????????????????
-
30??? Expectorants
- ???????????
- ???????,????????
- ? ??????????????
31??? Expectorants
- 1.???????
- ammonium chloride ???
- guaifenesine ???????
- potassium iodide ???
- ipecac syrup ????
- ?????????????
- 2.Mucolytics ?????
- acetylcysteine ??????,???
- bromhexine ???,???
32Classification of Mucolytics
- (1) ??????????????? ???????????
- (2) ??????????????????,??????????????????????????
? - (3) ???
- (4) ?????????
33???ammonium chloride
- ?????,?????,??????????,????,???
- ?????????
- ????????????????
- ??????????????????????????
34?????? Acetylcysteine (???)
- ??????N-????,??????????????????,?????????????,????
????,????? - ?????????????????
- ????????,???????,??????
35?????? Acetylcysteine (???)
- ?????,???????,????????,???????????????????
- ??????(penicillin)?
- ????(cephalosporin)?
- ???(tetracycline)??,??????????
36???(Antitussives)
37???(antitussives)
- ???????,?????????, ?????,??????
- Two Basic Types of Cough
- Productive Cough Non-Productive
Cough - Congested cough Dry/Hacking
cough - removes excessive self-feed
- secretions
- DONT USE USE
ANTITISSIVES - ANTITUSSIVES
38???(antitussives)
- Central antitussives
- Narcotic ???(Opioids ???)
- codeine ???
- Non-narcotic ????(Non-opioids ????)
- dextromethorphan ????
- pentoxyverine ????,???
- Peripheral antitussives
- benzonatate ????
39??? codeine
- Strongly effective cough suppressant, 1/4
morphine - Use for dry cough
- Produce constipation, nausea and respiratory
depression (60 mg). - Addictive liability
- Rarely recommended for children.
- NOT for cough accompanied with excessive
secretions.
40Dextromethorphan ????
- The most popular antitussives
- Selectively depresses the cough center in the
medulla - 1530 mg 815 mg codeine as an antitussive
- Therapeutic effect dry cough
- No respiratory depression, no euphoria and
physical dependence - Adverse effects are mild and rare dizziness,
drowsiness, nausea
41??? pentoxyverine
- Selectively depresses the cough center, 1/3
codeineatropine-like effect local anesthetic - ?????????????????????????
- Therapeutic effect dry coughgood for children
- ??????
42Peripheral Antitussives
- ??? narcotine
- ???? benzonatate
- ???????????????????,??????????
43Thanks!