BENHA UNIVERSITY, CREDIT HOURS SYSTEM
PHARMACOLOGY, DIGESTIVE SYSTEM (PHA311)
FOR STUDENTS ENROLLED IN PHARMACOLOGY PROGRAMS
1. DEMULCENTS
Def.:
These are the drugs which coat the mucous membranes of alimentary tract protecting them from irritation and
producing calming and soothing effects.
Mode of action:
Demulcents act mechanically by forming a coat onto mucous membranes protecting the underlying cells from
further irritation.
Members:
Demulcents can be classified according to their source into:
1. Gums: as gum acacia and gum tragacanth.
2. Sugars: as honey and treacle (molasses).
3. Vegetable oils: as cotton seed and olive oils.
4. Animal proteins: as egg albumin, gelatin and milk.
5. Insoluble salts: as Aluminium silicate (kaolin).
6. Glycerol.
Therapeutic uses:
1. Mild inflammation of alimentary tract as conditions of stomatitis, pharyngitis, gastritis and enteritis.
2. Poisoning with irritant drugs.
3. In drug preparations to mask the disagreeable taste of certain ingredients.
2. SIALAGOGUES & ANTISIALAGOGUES
2.1. SIALAGOGUES (SIALICS)
Def.:
These are the drugs which increase the volume and fluidity of saliva.
Members:
Sialics can be classified according to their mode of action into 3 groups:
1. Reflex sialics: which reflexly stimulate the salivary secretory centers by mild irritation of taste buds
and mucous membranes of upper digestive tract.
They include nauseant and bitter agents such as quassia, calumba and mustard.
Digestive System Pharmacology Surviving Revision
, BENHA UNIVERSITY, CREDIT HOURS SYSTEM
2. Direct sialics: which act directly on the salivary gland cells during their excretion irritating them.
Examples are potassium iodide and salicylates.
3. Cholinomimetics: which stimulate the parasympathetic division supplying salivary glands either
centrally as nicotine or peripherally as pilocarpine.
Therapeutic uses:
1. Xerostomia.
2. Debility and anorexia.
3. Atropine poisoning.
2.2. ANTISIALAGOGUES (ANTISIALICS)
Def.:
These are the drugs which decrease the volume and fluidity of saliva.
Members:
Antisialics can be classified according to their mode of action into 2 groups:
1. Astringents: which precipitate soluble proteins in saliva as tannic acid.
2. Cholinolytics: which block the response to the parasympathetic division of salivary glands (M-
receptor blockers) as atropine and hyoscine.
Therapeutic uses:
1. Pre-anesthetic medication to guard against asphyxia.
2. Certain diseases characterized by salivation and ulceration of oral cavity as F.M.D.
3. STOMACHICS
(APPETIZERS)
Def.:
These are the drugs which improve the appetite especially when depressed.
Mode of action:
Stomachics act by stimulating taste buds in the tongue leading to reflex increasing of alimentary secretions for
better digestion.
Members:
Stomachics can be classified according to their nature into:
1. Spices: as pepper.
2. Flavors: as volatile oils.
Digestive System Pharmacology Surviving Revision
, BENHA UNIVERSITY, CREDIT HOURS SYSTEM
3. Bitters: including,
a. Simple bitters that contain bitter principle(s) as Quasia and Qalumba.
b. Aromatic bitters that contain bitter principle(s) in addition to volatile oil(s) such as ginger,
cardamom, cinnamon, lemon peel extract and orange peel extract.
c. Alkaloidal bitters are alkaloids of bitter taste as quinine and strychnine (very small dose).
d. Astringent bitters that contain tannic acid as Cosparia.
Therapeutic uses:
Anorexia, debility, cachexia and anemia to improve body nutritional condition. They are given
shortly before meals.
4. DIGESTANTS
Def.:
These are the drugs which improve digestion process. They are usually given in the middle of the meal.
Members:
a. Stomachics.
b. Digestive enzymes as pepsin and papain.
c. Extracts that contain digestive enzymes such as pancreatin (mixture of trypsin, amylopsin and
lipase).
d. Diluted HCl or glutamic acid HCl orally.
Therapeutic uses:
1. Dyspepsia.
2. Achlorhydria.
3. Debility, cachexia and anemia.
Digestive System Pharmacology Surviving Revision
PHARMACOLOGY, DIGESTIVE SYSTEM (PHA311)
FOR STUDENTS ENROLLED IN PHARMACOLOGY PROGRAMS
1. DEMULCENTS
Def.:
These are the drugs which coat the mucous membranes of alimentary tract protecting them from irritation and
producing calming and soothing effects.
Mode of action:
Demulcents act mechanically by forming a coat onto mucous membranes protecting the underlying cells from
further irritation.
Members:
Demulcents can be classified according to their source into:
1. Gums: as gum acacia and gum tragacanth.
2. Sugars: as honey and treacle (molasses).
3. Vegetable oils: as cotton seed and olive oils.
4. Animal proteins: as egg albumin, gelatin and milk.
5. Insoluble salts: as Aluminium silicate (kaolin).
6. Glycerol.
Therapeutic uses:
1. Mild inflammation of alimentary tract as conditions of stomatitis, pharyngitis, gastritis and enteritis.
2. Poisoning with irritant drugs.
3. In drug preparations to mask the disagreeable taste of certain ingredients.
2. SIALAGOGUES & ANTISIALAGOGUES
2.1. SIALAGOGUES (SIALICS)
Def.:
These are the drugs which increase the volume and fluidity of saliva.
Members:
Sialics can be classified according to their mode of action into 3 groups:
1. Reflex sialics: which reflexly stimulate the salivary secretory centers by mild irritation of taste buds
and mucous membranes of upper digestive tract.
They include nauseant and bitter agents such as quassia, calumba and mustard.
Digestive System Pharmacology Surviving Revision
, BENHA UNIVERSITY, CREDIT HOURS SYSTEM
2. Direct sialics: which act directly on the salivary gland cells during their excretion irritating them.
Examples are potassium iodide and salicylates.
3. Cholinomimetics: which stimulate the parasympathetic division supplying salivary glands either
centrally as nicotine or peripherally as pilocarpine.
Therapeutic uses:
1. Xerostomia.
2. Debility and anorexia.
3. Atropine poisoning.
2.2. ANTISIALAGOGUES (ANTISIALICS)
Def.:
These are the drugs which decrease the volume and fluidity of saliva.
Members:
Antisialics can be classified according to their mode of action into 2 groups:
1. Astringents: which precipitate soluble proteins in saliva as tannic acid.
2. Cholinolytics: which block the response to the parasympathetic division of salivary glands (M-
receptor blockers) as atropine and hyoscine.
Therapeutic uses:
1. Pre-anesthetic medication to guard against asphyxia.
2. Certain diseases characterized by salivation and ulceration of oral cavity as F.M.D.
3. STOMACHICS
(APPETIZERS)
Def.:
These are the drugs which improve the appetite especially when depressed.
Mode of action:
Stomachics act by stimulating taste buds in the tongue leading to reflex increasing of alimentary secretions for
better digestion.
Members:
Stomachics can be classified according to their nature into:
1. Spices: as pepper.
2. Flavors: as volatile oils.
Digestive System Pharmacology Surviving Revision
, BENHA UNIVERSITY, CREDIT HOURS SYSTEM
3. Bitters: including,
a. Simple bitters that contain bitter principle(s) as Quasia and Qalumba.
b. Aromatic bitters that contain bitter principle(s) in addition to volatile oil(s) such as ginger,
cardamom, cinnamon, lemon peel extract and orange peel extract.
c. Alkaloidal bitters are alkaloids of bitter taste as quinine and strychnine (very small dose).
d. Astringent bitters that contain tannic acid as Cosparia.
Therapeutic uses:
Anorexia, debility, cachexia and anemia to improve body nutritional condition. They are given
shortly before meals.
4. DIGESTANTS
Def.:
These are the drugs which improve digestion process. They are usually given in the middle of the meal.
Members:
a. Stomachics.
b. Digestive enzymes as pepsin and papain.
c. Extracts that contain digestive enzymes such as pancreatin (mixture of trypsin, amylopsin and
lipase).
d. Diluted HCl or glutamic acid HCl orally.
Therapeutic uses:
1. Dyspepsia.
2. Achlorhydria.
3. Debility, cachexia and anemia.
Digestive System Pharmacology Surviving Revision
