Expectorants , sedative expectorants, stimulant expectorants, classification of expectorants, potassium iodide, medicinal uses of potassium iodide, Assay of ammonium chloride, medicinal uses of ammonium chloride

2. EXPECTORANT
An expectorant
Increases the amount of water in
mucousal secretions
Loosens up / thinning up of
mucus
Allows easy elimination
of mucus on coughing
CLASSIFICATION OF EXPECTORANTS
Depending upon mechanism of action
1. Sedative expectorants 2. Stimulant expectorants

3. 1. SEDATIVE EXPECTORANTS
These drugs irritate gastric mucosa and stimulate the release of
Histamine and Acetylcholine (along with gastrin). The released
Histamine and Ach combines with H-1 receptor and muscuranic
receptor respectively in the lungs, causing bronchoconstriction
and associated higher mucus production from the secretory cells
that lines the bronchioles.
PRINCIPLE: Indirectly acting expectorant
STIMULATION OF GASTRIC REFLEX
Eg: Bitter drugs such as Ipecac, Senega and Indian Squill
2. STIMULANT EXPECTORANT
PRINCIPLE: Directly acting expectorants
Stimulation of respiratory mucosal cells
These drugs directly irritate the respiratory mucosal cells.
This results in the production of more mucus which can be
easily eliminated out from the lungs through coughing
Eg: Ammonium Chloride, Pottasium Iodide, Sodium Citrate,
Antimony Pottasium tartarate

4. Pottasium Iodide
2. White cubical
crystals
3. Odourless
4. Saline followed by
bitter taste
6. M.P. = 681°C
5. Highly soluble in
water. Slightly soluble in
ethanol
1. Mol. Formula: KI
1. Stimulant Expectorant:
Directly irritates respiratory
mucousal layer to initiate more
mucus production. This results
in thinning of the mucus and
easier elimination of mucus
from lungs through coughing.
2. As a Dietary
supplement in
Iodine
deficiency and
Cretenism.
3. Used
to
Iodize
table
salt

5. 3.
Thyroprotective
activity: To
protect healthy
thyroid gland
cells from
radioactive
iodine (blocks
thyroid gland
cells from
absorbing
radioactive
iodine that is
used in cancer).
4. In Thyrotoxicosis (hyperthyrodism) and Grave’s
disease until surgery can be performed. KI
decreases the amount of thyroid hormones and
reduced the amount of blood flow within the gland.
In a radiation exposure emergency, such as leak
out of radioactive material from a nuclear
power plant or a nuclear bomb explosion, KI
tablets are given to protect thyroid gland from
radioactive 131I which can cause thyroid cancer.
AMMONIUM CHLORIDE
White Crystals
Odourless
Soluble in water, ethanol,
methanol and glycerol
Mp = 338°C
Bp = 520°C

6. ASSAY OF AMMONIUM CHLORIDE
PRINCIPLE: INDIRECT FORMAL ACID-BASE TITRATION
1. NH4Cl in conical flask is reacted with
previously nuetralized HCHO solution.
The reaction results in the liberation of
equivalent amount of HCl.
2. The equivalent amount of HCl liberated is
then titrated against NaOH using
phenolpthalien as indicator.
4NH4Cl + 6HCH0 (CH2)6H4 + 4HCl
+6H20
HCl + NaOH NaCl + H20
3. When whole of the HCl has reacted with NaOH, the next drop of NaOH will make the
contents of the flask alkali in pH. At alkali pH, Phelopthalien will be converted into its ionic
form which is pink in color.
NaOH(next drop) + In(colorless) In-(pink color)

7. PROCEDURE
After 2 Minutes….

8. Equivalent Weight Factor
Each ml of 0.1N NaOH Ξ 0.005349 g of NH4Cl
6. Calculate the percentage of NH4Cl present by
putting values in the following equation
MEDICINAL USES OF AMMONIUM CHLORIDE
1. As Stimulant Expectorant
Irritates bronchial mucosa,
thereby increasing the
production of mucosal fluid.
The higher volume of mucosal
fluid is easier to cough up and
is easier to be eliminated from
Respiratory tract.
2. In hypochlorhydria and
achlorhydria: Patients are
administered NH4Cl so as to as to
provide for the necessary acidity for
the proper digestion of food.

9. 3. As systemic
acidifier
Intravenous
Ammonium
Chloride is
given for this
purpose.
NH4Cl is
oxidized in
the liver to
ammonia
and HCl. The
liberated HCl
neutralizes
the excess
alkali in the
blood.
HCl which is a metabolic product of NH4Cl is filtered
off the blood through the kidney resulting in the
formation of Acidic urine which prevents the growth of
bacteria in urinary tract.
4. FOR UTI’s
NH4Cl is given orally.
Failure to acidify urine
below a pH of 5.5
indicates dRTA or
incomplete dRTA
(Inability of alpha
intercalated cells to
secrete acid).
5. In Oral Acid Loading
Test (diagnosis of distal
renal tubular acidosis).
In larger doses,
NH4Cl can induce
nausea and
vomiting by
irritation of gastric
mucosa.
6. As Emetic
NH4Cl injection in
isotonic NaCl
solution is indicated
in Hypochloremic
states
7. In Hypochloremia

10. THANK YOU….