Pharmaceutics -1 Suppositories
✯Suppositories✯
★ A unit solid dosage form of medicament meant for insertion into body cavity other than mouth is known as suppositories.
★ It can be inserted into rectum ( rectal suppositories) vagina ( vaginal suppositories) , urethra ( urethral suppositories).
★ It dissolve or melt at body temperature.
★ After melting or dissolution it produces systemic and local effect.
★ The medicament is incorporated into the suppositories bases.
★ Suppositories are available in a variety of shapes , sizes and weight.
Advantages-;
★ These can be easily given to children or all age group patient, and unconscious patient.
★ These produce systemic as well as local effect.
★ These exert direct and rapid action.
★ These facilitate the evacuation of bowl.
★ These are unit dosage form of drugs.
★ Drugs which irritate GIT , causes vometing, distroyed by pH and gastric juice easily administered by suppositories.
★ These form shows sustained release.
Disadvantages-;
★ Irritant drugs can not be administered by this route .
★ They cause embarrassment to the patient.
★ They require refregeration for storage.
★ They cannot be formulated readily.
Types of suppositories-;
According to their route of administration they are following types—
1. Rectal suppositories
2. Vaginal suppositories
3. Urethral suppositories
4. Nasal suppositories
5. Ear suppositories
1. Rectal suppositories-;
★ These meant for insertion in rectum.
★ They produce systemic effect.
★ Theobroma oil base used for formulation.
★ Usually they are 1-2gm in weight.
★ They have cone or torpedo shape.
2. Vaginal suppositories-;
★ These are meant for insertion in vagina.
★ They are also called pessaries.
★ They produces local effect.
★ Glycero- gelatin used as base.
★ They are 4- 8 gm in weight.
★ They have conical, rod shape .
3. Nasal suppositories-;
★ They are also known as nasal bougies.
★ They are meant for insertion is nasal .
★ They are thin & cylindrical in shape .
★ Glycero-gelatin base used for formulation.
★ They are 1gm in weight & 9- 10 cm long .
4. Urethral suppositories-;
★ Meant for insertion in urethra also called urethral bougies.
★ They are long , thin & cylindrical in shape.
★ One end is round for proper insertion.
★ They have 2- 4 gm weight.
★ These suppositories are rarely used.
5. Ear suppositories-;
★ They are meant for insertion in ear.
★ also called aurinaria.
★ They are rarely used.
★ Theobroma oil base used for formulation.
★ They are long , thin & cylindrical, in shape.
★ They have about 1gm .
Suppositories bases-;
Number of different bases are used in preparation of suppositories the ideal properties of suppositories bases are—
* It should be inert .
* It should be non- irritating .
* It should be non- sensitizing.
* It should be melt at body temperature.
* It should be compatible with variety of drug.
* It should release the drug readily.
* It should have wetting & emulsifying properties.
* It should be moldeble.
* It should be stable at storage.
Types of suppositories bases-;
Suppositories bases are classified into 3 categories—
1. Oleaginous base ( fatty base )
2. Aqueous base ( water soluble)
3. Emulsifying base.
1. Oleaginous base-;
a. Theobroma oil or cocoa butter-;
★ It is most satisfactory base for suppositories.
★ It is most widely used base.
★ It may exit in — α form , ẞ form and 𝛾 form.
α form - have melting point- 24°C
ẞ form - have melting point - 35-36°C
𝛾 form - have melting point- 18°C
b. Emulsified Theobroma oil-;
★ It is used when large quantities of aqueous solution are used.
★ It contains 5% glyceryl monostearate ,10% lunette wax , 2.3% cetyl alcohol, 4% beeswax.
c. Hydrogenated oils-;
★ It is produced by hydrogenation of oils like - cotton seed oil , coconut oil , palm oil etc.
★ It is good resistant power for oxidation.
★ Have good lubrication power.
★ Produce colourless, odour less suppositories.
2. Aqueous bases ( water soluble) -;
a. Glycero-gelatin-;
★ It is mixture of glycerine gelatin and water.
★ Used for preparation of pessaries.
b. Soap glycerine base-;
★ Soap is used instead of glycerine.
★ Formulation of suppositories is different because it is very hygroscopic in nature.
c. Polyethylene glycol (PEG) base-;
★ It is called carbo waxes .
★ It is non-irritating , chemical stable & inert in nature.
3. Emulsifying bases-;
a. Witepsol-;
★ It is triglyceride of saturated vegetable acid.
★ During formulation of suppositories more lubrication are needed.
b. Massuppol -;
★ It is also called Lauric acid.
★ Made by glyceryl esters.
★ They are non irritating, solidefy rapidly has good stability.
Method of preparation-;
1. Hand rolling method
2. Cold compression method
3. Hot process or fusion method
4. Automatic mould machine method.
1. Hand rolling method-;
★ It is the oldest method of formulation of suppositories.
A damp mass is formulated by triturating cocoa butter & drug in mortar
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Mass converted into a ball by rolling in hand.
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The ball then rolled into uniform cylinder
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Cylindrical form than cut into suitable number of pieces
2. Cold compression method-;
Grated mass of suppository base and medicament are mixed together
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The prepared mass is than forced into a mould under pressure
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The mould is then removed, open and replaced
3. Hot process or fusion method-;
It is applied for the formulation of all types of suppositories.
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Melting the suppositories base
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Dispersing or dissolving of the drugs in the melted base
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After proper mixing of base and drug , mixture is removed from heating
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Mixture is poured into a Suppositories mold
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After cooling suppositories are removed from mold
4. Automatic molding machine method-;
★ This is modern method of preparation.
★ Molding is completely automated done by machine.
★ Typical rotary machine turn out 3500—6000 suppository/ hrs.
Evaluation of suppositories-;
Suppository are evaluated by the following tests—
1. Test of appearance-;
★ All the suppository should be uniform in size and shape with a elegant appearance.
★ Individual suppository should be checked carefully.
2. Test of physical strength-;
★ In the test tensile strength of suppository is measured.
★ Tensile strength indicate maximum tolerable force of suppository.
★ Tolerable force support during production, packing and handling.
3. Test of dissolution rate-;
★ Dissolution rate indicate amount of dosage for get dissolve in body fluid in unit time.
★ Two apparatus are available for testing the dissolution test—
a. Suppository dialysis cell.
b. Stationary basket - Rotating paddle apparatus ( USP Dissolution test apparatus).
4. Test of melting range -;
a. Macro melting range -;
★ It is the time taken by the entire suppository to melt in a constant water bath.
★ In this testing tablet disintegration apparatus is used.
b. Micro melting range-;
★ Melting range of fatty base is measured in capillary tubes.
5. Test of softening time-;
★ Softening time is defined as the time at which the suppository melts completely at a definite temperature.
6. Test of uniformity of drug content-;
★ This test is used to check uniformity of mixed suppository mass.
★ All suppository should contain the same labelled quantity of drugs.
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