Laxatives are drugs that relieve constipation by losing stools or inducing a bowel movement. Some laxatives are also used before bowel procedures or examination. Laxatives come as pills, capsules, liquids, foods, gums, and suppositories. Drugs are Aloe, Rhubarb, Castor oil, Isabgol, Senna.

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LAXATIVES
Prepared by
Shivanee Vyas
Assistant Professor
SVKM’s NMIMS, School of Pharmacy and Technology Management

2. LAXATIVE
• Laxatives are drugs that relieve constipation by losing stools or inducing a
bowel movement.
• Some laxatives are also used before bowel procedures or examination.
• Laxatives come as pills, capsules, liquids, foods, gums, and suppositories.
• Drugs are
 Aloe,
 Rhubarb,
 Castor oil,
 Isabgol,
 Senna.
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3. ALOE
• Aloe Vera is a plant species of the aloe genus. If grows widely in tropical
climate and is also cultivated due to its agricultural and medicinal values.
• Synonym: Aloe, Alovera, Guarpatha
• Biological Source: It consist of dried juice of leaves of Aloe
barbadensis Miller and Aloe Africana.
• Family: Liliaceae.
• Geographical Source: Most of the species of aloe are indigenous to
Africa. But now introduced into West Indies and Europe. It is cultivated
through India but especially in North west Himalayas.
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4. • PREPARATION: Various methods are used to prepare aloes commercially in
Africa, as well as in west indies. Following is the general method of
preparation.
• The leaves are transversely cut at the base and the incised ends placed
downwards in a ‘V’ shaped trough having a hole at its bottom. The latex is
evaporated in a kettle made of copper where it gets solidified. When the latex is
concentrated gradually and then cooled slowly, it gives rise to an opaque
product. The aloe thus obtained is termed as ‘hepatic’ or ‘livery’ aloe.
• If the latex is concentrated rapidly, followed by sudden cooling the resulting
product appears to be transparent and relatively brittle in nature. The broken
surface has a glassy surface. Such a product is commonly known as ‘lucid’ or
‘glassy’ aloe.
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5. • MORPHOLOGICAL CHARACTERS:
 Colour: Depends upon variety From which it
is obtained. It is Green to dark brownish black
in colour.
 Odour: Characteristic
 Taste: Bitter taste
 Size: It is available in various sizes.
 Solubility: It is entirely soluble in 60% alcohol
and it partially soluble in water.
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• CHEMICAL CONSTITUENTS: All variety of aloes a yellow coloured crystalline
substance known as barbloin (c-glycoside), resin & aloe – emodin. Isobarbalion is
present in curacao and cape aloes. Cap aloes are characterized by the presence of an
amorphous compound β-barbalion, aloinosides A & B.

6. • IDENTIFICATION TEST:
1. Borax Test: To 5 ml of the above test solution add 0.2 gm of pure borax and heat
gently till it gets dissolved. Transfer a few drops of the resulting solution into a test
tube filled with distilled water, the appearance of a green colored fluorescence due
to the formation of aloe emodin anthranol shows its presence.
2. Bromine Test: When equal volumes of the test solution and bromine solution are
mixed together, it yields a pale-yellow precipitate due to the production of
tetrabromaloin.
3. Nitric Acid Test: The Test solution of aloes when made to react with nitric acid, it
gives Deep brownish red to pale brownish yellow.
4. Cupraloin Test: To 10 ml of a 0.4% (w/v) aqueous solution of aloe add a drop of
the saturated solution of copper sulphate, immediately followed by 1gm of NaCl
and 20 drops of ethanol (90% v/v). It produces a wine red colour lasting for few
hours.
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7. • USES:
1. Though, both aloes and aloin are official drugs, mostly used as a purgative by
exerting its action mainly on colon.
2. Aloes find its usefulness as an external aid to painful inflammatory action.
3. It constitutes an important ingredient in the ‘Compound Tincture of
Benzoin’ (or Friar’s Balsam).
4. Aloe gel are used in the treatment and cure of radiation burns or sun burn to get
immediate relief from itching and pains.
5. As a hair tonic.
6. It stimulates the growth of hairs.
7. It is also used in acne, pimples etc.
8. It is also used as a moisturizers.
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8. Rhubarb
• Biological Source: Dried underground parts (rhizome and root) of Rheum
palmatum.
• Family: Polygonaceae.
• Geographical Source: Rheum officinale or Rheum palmatum are grown in China
whereas the other species Rheum webbianum or Rheum
emodi are native to India, Pakistan or Nepal.
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9. • MORPHOLOGICAL CHARACTERS:
 Colour: Brown or yellow
 Odour: aromatic
 Taste: bitter and slightly astringent
 Size: 3 to 12 cm long and 3 to 8 cm in diameter
• CHEMICAL CONSTITUENTS: Rhubarb mainly contains 2.0 to 4.5
percent of anthraquinone glycosides, which include aloe-emodin,
chrysophanol, physcion, rhein and their derivatives. In addition to these
glycosides, Rhubarb also contains glucogallin, eallic acid, rheinotannic acid,
catechin, starch, sugars, fat, pectin and calcium oxalate.
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10. • PREPARATION
The rhizomes are collected either in spring or in autumn from 6 to 10 year old
plants. These are duly cleaned, and dried. The relatively larger rhizomes are cut
into small pieces either longitudinally or transversely. The cut fragments are dried
in the shade. They are also dried artificially in an atmosphere of hot wooden boxes
and exported for commercial consumption.
• CHEMICAL TESTS
1. The Rhubarb powder on being treated with ammonia gives rise to a pink
coloration.
2. Rhubarb gives a blood-red coloration with 5% potassium hydroxide.
3. It gives a positive indication with modified Borntrager’s test (see under Aloes).
• Uses
1. It is used mainly in the form of an ointment in the treatment and cure of
psoriasis.
2. It is employed as a bitter stomachic in the treatment of diarrhoea.
3. It is also used as a purgative.
• SUBSTITUTES AND ADULTERANTS:
English Rhubarb (Rheum Officinale) and Indian Rhubarb (Rheum emodz) are
used as substitutes, while Rhapontic Rhubarb (Rheum rhaponticum) and the stock
roots of Rumex alpinus and Rumex obtusifolius are used as adulterants of the
official drug.
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11. Castor oil
• SYNONYMS: Ricinus oil, Oleum ricini.
• BIOLOGICAL SOURCE: Castor oil is a fixed oil obtained by cold
expression of the seeds of Ricinus Communis.
• FAMILY: Euphorbiaceae.
• GEOGRAPHICAL SOURCE : Castor seeds are produced in all tropical and
subtropical countries like Brazil, USA, Thailand, Romania, India.
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12. • MORPHOLOGICAL CHARACTERS:
 Colour : Pale yellow or colourless liquid.
 Odour : Slight and characteristic
 Taste : bland then slightly acrid & nauseating it is viscous and transparent liquid
 Solubility: It is soluble in alcohol. Miscible in chloroform, solvent ether, glacial
acetic acid and petroleum ether.
• CHEMICAL CONSTITUENTS: Castor oil contains triglyceride of ricinoleic
acid 80%. The viscosity of castor oil is due to ricinoleic acid. Other glycerides are
isoricinoleic, linoleic, stearic and isostearic acid. It contains heptaldehyde, sebacic
acid.
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Ricinoleic acid

13. • PREPARATION:
Castor oil is obtained from castor seeds. Usually the oil is obtained after removing the
seed coat but sometimes it removing seed coats; seeds are placed in grooved rollers and
crushed when taste becomes loosened and is removed by blowing in air current.
The kernels are placed in oil-expellers and expressed at room temperature with 1 to 2
tons pressure per square inch till about 30% oil is obtained. Oil is filtered but it
contains a poisonous principle ricin a ton albumin and enzyme lipase. To remove ricin,
steam is passed into the oil at a temperature between 80 to 100°C, when ricin is
coagulated and precipitated and lipase becomes inactive. Oil is then filtered. This oil
has 145 acidity and only this cold drawn castor oil is used for medicinal purposes.
• CHEMICAL TEST:
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Test Observation Inference
Castor oil + petroleum
ether
Completely soluble in
petroleum ether
Castor oil is present
Castor oil + equal
volume of alcohol
Clear liquid at cool at
0°c for (3 hours)
Castor oil is present
• USES : Castor oil is used as cathartic. It is used as laxative, lubricant, in paints, enamel,
varnish, grease, polish, printing ink, aromatic castor oil, or in the form of capsules,
creams, jellies, lipsticks, perfumed hair oil, soap etc. also used as hair tonic.

14. Isabgol
• SYNONYMS: Plantage seed, Psyllium husk, Ashwakarna, Isapgol
• BIOLOGICAL SOURCE: It consist of dried seeds of the plant Plantego
Ovata.
• FAMILY: Plantagenaceae.
• GEOGRAPHICAL SOURCE: The plant is cultivated largely in Gujarat,
Punjab and South Rajasthan. The factory for preparation of Husk is located
at Sidhpur in North Gujarat and Maharashtra in Pune. About 30 thousand
hectares of area is said to be under cultivation of the drug in India. The dry
seeds of Isabgol is obtained from a 4 month old plant.
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15. • MORPHOLOGICAL CHARACTERS:
 Colour: Yellowish Brown
 Odour: Odourless
 Taste: Gum like (Mucilaginous)
 Shape: Oval
 Size: 1.6 to 3.4mm length and 1.5 to 1.76mm width
• CHEMICAL CONSTITUENTS: The main chemical constituent founding is
mucilage which is pentosan. It also contains xylose, arabinose, fixed oil, protein
and amino acid.
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16. • IDENTIFICATION TEST
• USES:
1. It is used as laxative in the treatment of chronic constipation.
2. Isabgol seed has cooling, laxative, demulcent, expectorant, emollient and
astringent properties.
3. It is used commonly in diarrhea, dysentery, ulcers.
4. It helps to reduce the risk of heart attack by decreasing serum cholesterol
through proper excretion of bile acids.
5. Isabgol seeds are also used in fever, burning sensations, skin problems, and in
affections of the bladder, urethra, and kidney.
6. It is used internally in thirst, cough. 16
Test Observation Inference
Isabgol+ Ruthenium
Red
Red colour Presence of Mucilage
Isabgol+ Thionine test
solution→ wait for 10
minutes and then wash
with alcohol
Mucilage turns Violate-
red
Presence of Mucilage

17. Senna
• Synonym: Indian senna, Senna Ki Patti, Sonamukhi, Alexandrian
• Biological Source: It consist of dried leaflets of Cassia Angustifolia.
• Family: Leguminosae
• Geographical source: Indian senna is cultivated and collected in India. Its
cultivation is mainly done in Tinnevelly, Madurai and Ramnathpuram districts
of Tamil Nadu. Cultivation is attempted in Cudappa district of Andhra Pradesh
and to some extent is collected from Kutch in Gujarat state and Rajasthan.
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18. • MORPHOLOGICAL CHARACTERS
 Color: Yellowish green
 Odor: Slight
 Taste: Mucilaginous and slightly bitter
 Size: 7-8mm in width & 25-60mm in length
• CHEMICAL CONSTITUENTS: Principal constituents of Senna are
anthraquinone glycosides, which include sennosides A, B, C and D rhein and
aloe-emodin. Senna also contains kaempferol and yellow flavonol).
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19. • IDENTIFICATION Test :
 Borntrager’s test:
The drug is boiled with dilute sulphuric acid,
Filtered and to the filtrate, benzene or ether or chloroform is added and
shaken well
The organic layer is separated to which ammonia is added slowly
The ammoniac layer shows pink to red due to presence of
Antraquinones glycosides.
• USES: Senna is used as purgative in constipation.
• Substitutes and adulterants: Substitutes and adulterants of Senna
include the leaves and leaflets of the following related plants: Cassia
obovata (Dog Senna), wild plants of C. angustifolia (Arabian Senna).
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