Pharmaceutical excipients are inert substances included in drug products that alter the functions and properties of active pharmaceutical ingredients. Excipients convert active compounds into suitable dosage forms and are essential for acceptable drug delivery. They aid manufacturing, protect drugs, enhance stability and bioavailability, and improve patient acceptability. Excipients are classified based on their functionality, origin, physical form, and route of administration. Careful consideration of excipient selection is important to avoid interactions that could compromise drug stability, effectiveness, or safety.

1. PHARMACEUTICAL
EXCIPIENTS
Dr. Kamlesh J. Wadher

2. Pharmaceutical Excipients:
.
Pharmaceutical excipients are pharmacologically
inert substances which are included in the
manufacturing process or are contained in a
finished pharmaceutical product dosage form to
alter the functions.
The word excipient is derived from the Latin excipere,
meaning ' except', which is simply explained as
'other than'.

3. • Excipients are the additives used to
convert pharmacologically active
compounds into pharmaceutical dosage
forms suitable for administration to
patients.
• Although excipients are the non-active
ingredients, they are essential in the
successful formulation of acceptable
dosage forms.

4. Role of Excipients:
Any substance other than the active drug which has
been appropriately evaluated for safety and is included
in a drug delivery system to either:
• Aid processing of the system during manufacture,
• Protect, support or enhance stability, bioavailability or
patient acceptability,
• Assist in product identification.
• Enhance any other attribute of the overall safety and
effectiveness of the drug product during storage or use.
• Assist in maintaining integrity of the product
• Improve stability
• Release Modification/ alteration

5. Ideal Characteristics of excipients
• It should be chemically and physically inert.
• It should not create any bioavaibility problems.
• It should not be toxic.
• It should be compatible with drug and other ingredients.
• It should be compatible with primary packaging materials.
• It should be organoleptically acceptable.
• Economic
• It should not have therapeutic activity of its own.
It should offer desired functionality

6. Advantages of using excipients :
• It improves the wetting property (surfactants).
Hydrocolloids may serve the purpose of
emulsifying, binding, gel forming agents.
• Increases the bulk of the drug.
• Provide stabilization of formulation(It serves as ph
adjuster, chelating agent, anti-oxidant).
• Improves organoleptic properties.
• It serves as vehicle for formulation.
• Patient Compliance -Tablets

7. Disadvantages of using excipients :
• May cause chemical interaction with drug (example:
amphetamine + sod. CMC = produce undesirable
complex ).
• Can cause bioavailability problems
• ( phenobarbital + oily vehical = cause less drug release).
• Can interact with packaging material to affect active
ingredient

8. Classification of excipients on
the basis of Functionality

9. A- SOLID DOSAGE FORM:
Tablets
:
• Diluents – lactose, mannitol , starch, sucrose,
dextrose etc.
• Binders – acacia, sorbitol , tragacanth , sodium
alginate, starch paste etc.
• Disintegrates – starch, cellulose, alginates,
microcrystalline cellulose, sodium starch glycolate ,
citric acid, tartaric acid etc.
• Lubricants – stearic acid and its salts, talc,
polyethylene glycol, mineral oil etc.

10. • Glidants and flow promoters – mg. stearates, talc, corn
starch etc.
• Colours – It may be natural or synthetic colours .
Natural colours are classified as:
• mineral – titanium dioxide, carbon black, prussian blue
etc. plant origin – chlorophyll, carotene, indigo etc.
• Animal origin – carminic acid (from coccus cacti), tyrian
purple (from snail) etc.

11. • Sweetners – sugar, saccharin, liquid glucose, cyclamates
etc.
• Flavours – menthol, cadamom , ginger, pineapple, orange
etc. These flavours may be ester, methyl salicylate ,
alcoho , glycerine & aldehyde in chemical nature.
• Tablet coating excipients – For sealing – shellac, cellulose
acetate phthalate etc.
• For sub-coating – sucrose, corn syrup, acacia, gelatin,
talc, calcium carbonate etc.
• For polishing – bees wax, carnauba wax, chlorinated wax
etc.
• Film forming – polyvinylpyrrolidone , polyvinyl alcohol,
CMC, MC, HPC, EC etc.

12. Capsules
•
• Body of capsule- gelatin, HPMC
• Diluents – lactose, mannitol , sorbitol , starch.
Glidant – talc.
• Antidusting agent – inert edible oil.
• Polishing agent – crystalline sodium chloride.
• Sealing and locking – water, acacia mucilage.

13. Semi-solid dosage forms (ointments,
suppositories, creams, pastes).
• Bases : Hydrocarbon – microcrystalline wax, paraffin
wax, petrolatum etc.
• Vegetable oils – sesame oil, olive oil, peanut oli etc.
• Animal fat – bees wax, lanolin, spermaceti wax etc.
• Alcohols – cetyl alcohol, stearyl alcohol, lauryl alcohol
etc.
• Acids – stearic acid, oleic acid, palmitic acid, myristic
acid etc. Esters – isopropyl myristicate , ethylene glycol,
ethyl oleate etc.
• Preservatives – benzoic acid, phenol, phenyl mercuric
nitrate, salicylic acid.
• Antioxidants – BHA, BHT, ascorbic acid, tocopherol ,
sodium bisulfite .

14. Liquid dosage forms: Syrup, suspension, emulsion :
• Aqueous vehicle – distill & purified water(water for injection), syrup
(acacia syrup, cherry syrup, cocoa syrup)
• Hydroalcoholic liquid – glycyrrhiza elixir, aromatic elixir.
• Alcoholic liquids – lemon tincture, orange tincture, peppermint spirit.
• Oily vehicle – cottonseed oil, castor oil, sesame oil.
• Surfactants – sodium lauryl sulphate , benzalkonium chloride, lauryl
, cetyl and stearyl aalcohols .
• Flavours - menthol, cadamom , ginger, pineapple, orange etc.
These flavours may be ester, methyl salicylate , alcoho , glycerine &
aldehyde in chemical nature.
• Sweetners – sugar, saccharin, liquid glucose, cyclamates etc.
• Colours – It may be natural or synthetic colours
•

15. • Preservatives – benzoic acid, phenol, phenyl mercuric
nitrate, salicylic acid.
• Antioxidants – BHA, BHT, ascorbic acid, tocopherol ,
sodium bisulfite . Injectables : Vehicle – sterile waterfor
injection, purified water, ethyl alcolhol , glycerine , PEG,
peanut oil , seasem oil, cottonseed oil.
• Stabilizer – EDTA Buffer – salts of acetate, citrate,
phosphates. Antioxidants – sodium bisulphite .
Preservatives – benzoic acid, phenol, phenyl mercuric
nitrate, salicylic acid, chlorobutol .
• Tonicity contributors – sodium chloride, borax Wetting,
suspending & emulsifying agent – tween-80, pluronic F-
68, sorbitan trioleate , CMC, PVP, lecithin

16. On the basis of Route of
Administration
• Oral Excipients
• Topical Excipients
• Parenteral Excipients

17. On the basis of origin
• Natural-
– Plants- starches
– Minerals- Mg. stearates
– Insects- Chitosam
– Animals- Gelatin
• Synthetic- HPMC, PVP

18. On the basis of physical form
• Solid- Lactose, MCC
• Liquids- Water, Oils, Propylene glycol
• Gases: Propellants

19. • Inorganic Chemicals
-Calcium Phosphates
-Calcium Carbonate
• -Calcium Sulfate
• Organic Chemicals
• Carbohydrates -Sugars
• Starch
• Cellulose
– CMC
– Microcrystalline Cellulose
• Petrochemicals
– Glycols
• Polyethylene Glycol
• Propylene Glycol
• Mineral Hydrocarbons
– Petrolatum
– Mineral Waxes
– Mineral Oils

20. Factor affecting the selection of
excipients:
1. Types of dosage formulation.
2. overall quality, stability, and effectiveness of product.
2. Compatibility of excipients with drug and the packaging
system.
3. Compatibility of excipients with the manufacturing
process.
For example, preservatives may be adsorbed by rubber tubes
or filters, acetate buffers will be lost during lyophilization
process, etc.
4. The amount or percentage of excipients that can be
added to the drug product.
Example cresol and phenol in conc. of 0.5%
5. Route of administration.
6. Cost

21. 7. Suitability of excipients with patients.
Example Dimethyl sulfoxide can cause stomach upset,
diarrhea, drowsiness, and headache.
Lactose unsuitable for people with lactose insufficiency,
galactosemia , or glucose/ galactose malabsorption
syndrome.
Organic mercury compounds can cause kidney damage
Parahydroxybenzoate and their esters known to cause
urticaria .
Generally delayed type reactions, such as contact
dermatitis Phenylalanine Harmful for people with
phenylketonuria

22. Source of Interactions
• Functional groups of excipients & API
• Impurities, residues & degradation products -
decompose API
• Microbial contamination
• - irritation of skin ,
• - mucosal sensitization,
• - effect the organoleptic characters of product

23. Types of Interactions
• Chemical interaction :
• Degradation of API – less therapeutic effect.
• Physical interactions :
• Dissolution rate
• Uniformity of dose
• Administration problem

24. Chemical Interactions
• Most of the chemical interactions are instantly
detectable.
• Example: Charge interactions of soluble and ionizable
excipients can interact with API.
• positive charge drugs like neomycin, polymycin leads to
precipitation in presence of Sodium alginate

25. Physical Interactions
• Adsorbing agents : Adsorbing agents are used to
increase effective surface area and optimize the
dissolution If forces of attraction are high, it leads to
improper dissolution profiles.
Eg: MCC +Bemazocaine
Moisture content : % Moisture content in formulations can
effect the dissolution profile incase of anhydrous API and
excipients.
Eg: anhydrous lactose, anhydrous sodium carbonate