There are two sorts of cough:
productive (the useful) when it expels
secretions or foreign material from the respiratory
tract
Useful cough should be allowed to serve its purpose and
suppressed only when it is exhausting the patient or is
dangerous, e.g. after eye surgery.
unproductive and persistent( the useless )
Useless persistent cough should be stopped.
Asthma, rhinosinusitis, oesophageal reflux
There are two sorts of cough:
productive (the useful) when it expels
secretions or foreign material from the respiratory
tract
Useful cough should be allowed to serve its purpose and
suppressed only when it is exhausting the patient or is
dangerous, e.g. after eye surgery.
unproductive and persistent( the useless )
Useless persistent cough should be stopped.
Asthma, rhinosinusitis, oesophageal reflux
Mechanism of cough
Stimulation of mechano-or chemoreceptors (throat, respiratory
passages or stretch receptors in lungs)
Afferent impulses to cough centre
(medulla)
Efferent impulses via parasympathetic & motor nerves
to diaphragm, intercostal muscles & lung
Increased contraction of diaghramatic, abdominal &
intercostal (ribs) muscles noisy expiration (cough)
Stimulation of mechano-or chemoreceptors (throat, respiratory
passages or stretch receptors in lungs)
Afferent impulses to cough centre
(medulla)
Efferent impulses via parasympathetic & motor nerves
to diaphragm, intercostal muscles & lung
Increased contraction of diaghramatic, abdominal &
intercostal (ribs) muscles noisy expiration (cough)
SITES OF ACTION FOR TREATMENT
Peripheral sites
On the afferent side of the cough reflex: by reducing
input of stimuli from throat, larynx, trachea
a warm moist atmosphere has a demulcent effect on the
pharynx.
On the efferent side of the cough reflex: to render
secretions more easily removable (mucolytics)
SITES OF ACTION FOR TREATMENT
Peripheral sites
On the afferent side of the cough reflex: by reducing
input of stimuli from throat, larynx, trachea
a warm moist atmosphere has a demulcent effect on the
pharynx.
On the efferent side of the cough reflex: to render
secretions more easily removable (mucolytics)
The best antitussive of all :is removal of the cause of
the cough itself, e.g. treatment of underlying
conditions such as
asthma
postnasal drip
gastrooesphageal reflux.
In patients with hypertension or cardiac failure, a
common cause of a dry cough is treatment with an
ACE inhibitor.
The best antitussive of all :is removal of the cause of
the cough itself, e.g. treatment of underlying
conditions such as
asthma
postnasal drip
gastrooesphageal reflux.
In patients with hypertension or cardiac failure, a
common cause of a dry cough is treatment with an
ACE inhibitor.
COUGH SUPPRESSION
Antitussives
1.
Peripheral antitussives
2.
Central antitussives
COUGH SUPPRESSION
Antitussives
1.
Peripheral antitussives
2.
Central antitussives
Peripheral antitussives
Demulcents
that soothingly coat the pharynx
Linctus(mainly sugar-based syrup).
Lozenges
Inhalation
Water aerosol inhalation
B
enzoin
to give the inhalation a therapeutic smell (aromatic
inhalation
Local anaesthetics block the mucosal cough receptors (modified
stretch receptors)
directly ,Nebulised lignocaine reduces coughing
during some type of bronchoscopy
in the cough that accompany bronchial carcinoma.
Peripheral antitussives
Demulcents
that soothingly coat the pharynx
Linctus(mainly sugar-based syrup).
Lozenges
Inhalation
Water aerosol inhalation
B
enzoin
to give the inhalation a therapeutic smell (aromatic
inhalation
Local anaesthetics block the mucosal cough receptors (modified
stretch receptors)
directly ,Nebulised lignocaine reduces coughing
during some type of bronchoscopy
in the cough that accompany bronchial carcinoma.
2- centrally acting Antitussives
The opioid analgesics are among the most effective drugs
for the suppression of cough(medullary cough centre itself)
at doses below those necessary to produce analgesia.
The receptors involved in the antitussive effect differ from
those associated with the other actions of opioids).
The opioid derivatives used as antitussives are
dextromethorphan, codeine, and noscapine
2- centrally acting Antitussives
The opioid analgesics are among the most effective drugs
for the suppression of cough(medullary cough centre itself)
at doses below those necessary to produce analgesia.
The receptors involved in the antitussive effect differ from
those associated with the other actions of opioids).
The opioid derivatives used as antitussives are
dextromethorphan, codeine, and noscapine
methadone or diamorphine linctus preferred
in patients with advanced bronchial carcinoma
pholcodine, ( nonsedating and nonaddictive), is
widely used
methadone or diamorphine linctus preferred
in patients with advanced bronchial carcinoma
pholcodine, ( nonsedating and nonaddictive), is
widely used
Dextromethorphan,
it is NMDA receptor antagonist
free of addictive properties and produces less constipation
than codeine.
The usual antitussive dose is 15-30 mg three or four times
daily.
Codeine, has antitussive action at doses lower than those
required for analgesia. Thus, 15 mg are usually sufficient to
relieve cough.
Dextromethorphan,
it is NMDA receptor antagonist
free of addictive properties and produces less constipation
than codeine.
The usual antitussive dose is 15-30 mg three or four times
daily.
Codeine, has antitussive action at doses lower than those
required for analgesia. Thus, 15 mg are usually sufficient to
relieve cough.
Antihistamines: Sedation reduces the sensitivity of the
cough reflex. older sedating antihistamines,
e.g. diphenhydramine often the doses needed causes
drowsiness so that combination with other drugs, such
as pholcodine and dextromethorphan,
In children cough is nearly always useful and sedation
at night is more effective than is codeine. A sedative
antihistamine (e.g. promethazine), sputum
thickening may be a disadvantage.
Antihistamines: Sedation reduces the sensitivity of the
cough reflex. older sedating antihistamines,
e.g. diphenhydramine often the doses needed causes
drowsiness so that combination with other drugs, such
as pholcodine and dextromethorphan,
In children cough is nearly always useful and sedation
at night is more effective than is codeine. A sedative
antihistamine (e.g. promethazine), sputum
thickening may be a disadvantage.
MUCOLYTICS AND EXPECTORANTS
Respiratory mucus consists largely of
water and its slimy character is due to glycoproteins
cross-linked together by disulphide bonds.
In pathological states much more mucus may be
produced; an exudate of plasma proteins which
bond with glycoproteins and form larger polymers
results in the mucus becoming more viscous.
MUCOLYTICS AND EXPECTORANTS
Respiratory mucus consists largely of
water and its slimy character is due to glycoproteins
cross-linked together by disulphide bonds.
In pathological states much more mucus may be
produced; an exudate of plasma proteins which
bond with glycoproteins and form larger polymers
results in the mucus becoming more viscous.
A mucolytic drug: is a drug that breaks down thick
mucus, making it thinner and easier to cough out.
Carbocisteine and mecystine
MOA :have free sulphydryl groups that open disulphide
bonds in mucus and reduce its viscosity.
orally administrated or by inhalation
uses :when viscous secretion is a problem (cystic fibrosis)
side effects:gastrointestinal irritation and allergic
reaction.
A mucolytic drug: is a drug that breaks down thick
mucus, making it thinner and easier to cough out.
Carbocisteine and mecystine
MOA :have free sulphydryl groups that open disulphide
bonds in mucus and reduce its viscosity.
orally administrated or by inhalation
uses :when viscous secretion is a problem (cystic fibrosis)
side effects:gastrointestinal irritation and allergic
reaction.
Bromhexine
Thinning & fragmentation of mucopolysaccaride
fibers
↑
volume & ↓ viscosity of sputum
Bromhexine
Thinning & fragmentation of mucopolysaccaride
fibers
↑
volume & ↓ viscosity of sputum
Dornase alfa is phosphorylated glycosylated
recombinant human deoxyribonuclease.
MOA:hydrolyzes the DNA present in sputum/mucus
of cystic fibrosis patients and reduces viscosity in the
lungs
It is given daily by inhalation
Dornase alfa is phosphorylated glycosylated
recombinant human deoxyribonuclease.
MOA:hydrolyzes the DNA present in sputum/mucus
of cystic fibrosis patients and reduces viscosity in the
lungs
It is given daily by inhalation
Expectorants
encourage productive cough by increasing the volume of
bronchial secretion;
The group includes:
guaiphenesin
Ipecacuanha
volatile oils
Expectorants
encourage productive cough by increasing the volume of
bronchial secretion;
The group includes:
guaiphenesin
Ipecacuanha
volatile oils
Guaiphenesin Expectorant drug usually taken by
mouth
Available as single & also in combination
MOA
=Increase the volume & reduce the viscosity of
secretion in trachea & bronchi
Guaiphenesin Expectorant drug usually taken by
mouth
Available as single & also in combination
MOA
=Increase the volume & reduce the viscosity of
secretion in trachea & bronchi
Choice for drug therapy for cough
• Simple suppression of useless cough
Codeine, pholcodine, dextromethorphan and
methadone
In pertussis infection (whooping cough), codeine and
atropine
• Simple suppression of useless cough
Codeine, pholcodine, dextromethorphan and
methadone
In pertussis infection (whooping cough), codeine and
atropine
• To increase bronchial secretion slightly and to
liquefy what is there
Water aerosol with or without menthol and benzoin
inhalation, or menthol and eucalyptus inhalation may
provide comfort harmlessly.
Carbocysteine or another mucolytic orally may
occasionally be useful.
• Cough originating in the pharyngeal region
lozenges or demulcents are used.
• To increase bronchial secretion slightly and to
liquefy what is there
Water aerosol with or without menthol and benzoin
inhalation, or menthol and eucalyptus inhalation may
provide comfort harmlessly.
Carbocysteine or another mucolytic orally may
occasionally be useful.
• Cough originating in the pharyngeal region
lozenges or demulcents are used.