Liniments

Liniments are solutions or mixture of various substances in oil, alcoholic solution of soap, or emulsions, intended for external application. They are applied with rubbing to the affected areas and that is why they were once called embrocations.

Dental liniments are solutions of active substances which are rubbed into the gums, but they are no longer official.

Liniments are usually applied to the skin with friction and rubbing, the oil and soap base providing for ease of application and massage. Alcoholic liniments are intended generally for their rubefacient, counterirritant, mildly astringent and penetrating effects. They penetrate the skin readily than the oil base. Therefore, oily liniments are milder in their action but are more useful when massage is desired. Some liniments are solely used as protective coating depending on the ingredients in the preparation. Liniments should not be applied on bruises and broken skin.

Liniments usually contain methyl salicylate, menthol and camphor in their preparations.

Example of Liniments and Their Preparation

 

Camphor Liniment, NF, BP

Other Names: Linimentum Camphoras or Camphorated Oil

Formula:

Camphor                  200 g

Cottonseed Oil         800 g

          To make        1000 g

Preparation

Place the cottonseed oil into a suitable dry flask or bottle, heat on a steam bath, add camphor and stopper the container securely. Agitate to dissolve the camphor without further heating.

Uses: Mild counterirritant for inflamed joints, sprains, rheumatism and in other inflammatory conditions such as cold in throat and chest, in infants and children.

Remarks: The liniment should never be prepared in an open dish, as much of the camphor will volatilize. Although “camphorated oil” is often applied to this liniment and also frequently to indicate “Camphor Injection” a sterile 10% solution of camphor in olive oil or other fixed oil and which is used hypodermically as a stimulant. The two products must not be confused.

Camphor and Soap Liniment, NF

Other Names: Linimentum Camphorae et Saponis, Soap Liniment, Liquid Opodeldoc and Camphorated Tincture of Soap.

Formula:

Camphor, in small pieces               45 g

Soap, dried and granulated             60 g

Rosemary Oil                                10 ml

Alcohol                                         700 ml

Purified Water, q.s.                    ________

          To make                             1000 ml

Preparation:

Dissolve camphor and rosemary oil in alcohol, add the soap and sufficient quantity of purified water to measure 1000ml. Agitate to dissolve the soap, set aside in a cool place for 24 hours and filter.

Uses: Local irritant, mild rubefacient, and weak local anesthetic for sprains, bruises and rheumatism. It also forms the basis for other liniments.

Remarks: The official hard soap should be used; soap made from animal oils will cause felatinization. If soap shaving from bar soap are used, dry thoroughly and then run thru a mill or grater.

Chloroform Liniment, NF

Other Name: Linimentum Chloroformi

Formula:

Chloroform                                   300 ml

Camphor and Soap Liniment        700 ml

            To make                           1000 ml

Preparation: Mix the ingredients by agitation

Uses: Applied to the skin as stimulant and rubefacient for the production of counterirritation in the treatment and relief of myalgias, neuralgias, and certain forms of involvement of joints and particular structures.

Inhalations and Inhalants

Inhalations are drugs or combinations of drugs administered through the nasal or oral respiratory route for local or systemic effect. These preparations are designed to carry the drug into the respiratory tree of the patient where its vapors give a prompt relief from symptoms of bronchial and nasal congestion. Nebulizers are suitable for administration of inhalation solutions only if they give droplets sufficiently fine and uniform in size so that the mist reaches the bronchioles.

Inhalations include also volatile and powdered medicaments and aerosols that are administered by the respiratory route with the aid of appropriate device. Pressurized aerosols produce fine mists hence possess basic advantages over the older nebulizers. The term inhalation is used commonly by the layman to represent preparations intended to be vaporized with the aid of heat, usually steam and inhaled. Vaporizer is used with a number of commercial available preparations of this type.

 Example of Inhalations

1.       Epinephrine Inhalations, USP – It is a solution of epinephrine in purified water prepared with the aid of hydrochloric acid. It contains in each 100 ml, 0.9 – 1.15 g of C₉H₁₃NO₃. It is used in therapy of bronchial asthmatic attacks. It shrinks the congested bronchial musoca and relaxes the bronchial musculature (adrenergic).

2.       Isoproterenol Hydrochloride Inhalation, USP – A solutions of isoproterenol hydrochloride in purified water made isotonic by the addition of sodium chloride. It contains 95 – 105% of the labeled amount of C₁₁H₁₇NO₃.HCl. It is used as a bronchial dilator to treat asthma. It affords a complete relief in mild or moderately severe asthma and is of value in status asthmaticus. Most effective is inhalation of a suitable aerosol at the onset of attack.

3.       Salbutamol (Albuterol) Solution for Nebulization – It is an antiasthma drug which contains 1mg/ml of Salbutamol.

4.       Budesonide Inhalation Solution for Nebulization – It is an antiasthma drug which contains 250mcg/ml of budesonide.

5.       Ipratropium Inhalation Solution for Nebulization – It is an antiasthma drug which contains 250mcg/ml of ipratropium.

6.       Fenoterol + Ipratropium Inhalation Solution for Nebulization – It is a combination of two antiasthma drugs which contains 50mcg and 20mcg, respectively, per 4 ml solution.

7.       Salbutamol + Ipratropium Inhalation Solution for Nebulization – it is a combination of two antiasthma drugs which contains 500mcg and 2.5mg, respectively, per 2.5ml of solution.

Inhalants

According to the NF XII, Inhalants are drugs or combination of drugs, which by virtue of their vapor pressure, can be carried by an air current into the nasal passages where they exert their effect. Inhaler is the device used for the administration of inhalants.

It is another group of products known also as inhalants or insufflation (but not official in the NF) consists of finely powdered or liquid drugs that are carried into the respiratory passages by the use of low pressure “aerosol” containers. The containers hold a solution or suspension of the drug in a liquefied propellant and when released through a suitable spray nozzle, a metered dose of the inhalant is propelled into the respiratory tract of the patient.

The official preparation is described as consisting of cylindrical rolls of suitable fibrous material impregnated with propylhexedrine, usually aromatized and contained in a suitable inhaler.

Example of Inhalants

1.  Propylhexedrine Inhalant, NF – It is a Benzedrex Inhaler consists of cylindrical rolls of suitable fibrous material impregnated with propylhexedrine usually aromatized and contained in a suitable inhaler. The inhaler contains 90 – 120% of the labeled amount of C₁₀H₂₁N.
2.  Salbutamol Metered Dose Inhalant – It is an inhalant which contains 100mcg of Salbutamol per actuation. It is used to treat asthma.

Glycerites

Glycerites are solutions or mixtures of medicinal substances in not less than 50% by weight of glycerin.  Most glycerites are viscous while some are of jelly-like consistency.

Some of the glycerites are used in their original form as medicinal agent while others are used to prepare aqueous and alcoholic dilutions of substances which are not readily soluble in water or alcohol. Glycerin of Phenol, BPC, 1963 is diluted with glycerin to form the pharmaceutical preparation, Ear Drops with Phenol, BPC 1963. Water should not be added to this preparation. It reacts with the phenol to produce a preparation which is caustic and consequently causes damage in the area of application.

Glycerites are hygroscopic and therefore, should be stored in tightly closed containers. Glycerin is a valuable pharmaceutical solvent forming permanent and concentrated solutions not otherwise obtainable.

EXAMPLES OF GLYCERITES AND THEIR PREPARATION

 

Starch Glycerites, NF

Other Names: Glyceratum Amyli and Starch Glycerin

Formula:

Starch                           100g

Benzoic Acid                 2 g

Purified water             200 ml

Glycerin                      700 ml

     To make about        1000g

Preparation:

Levigate thoroughly the starch and benzoic acid with the purified water in a porcelain dish until a smooth mixture is produced then add the glycerin and mix well. Heat the mixture of a sand bath to a temperature between 140o – 144o with constant but gentle stirring until a translucent, jelly-like mass are results. Strain through muslin.

Starch glycerite should be freshly prepared.

Possible Uses: Emollient, sometimes used as a substitute for fatty ointment vehicles and as a pill excipient.

Dose: Topically as required.

Tannic Acid Glycerite, NF

Other Names: Glyceritum Acidi Tannici; Glycerite of Tannin; Tannic Acid Glycerin

Formula:

Tannic Acid                                   20 g

Exsiccated Sodium Sulfite           0.2 g

Sodium Citrate                                1 g

Glycerin, q.s.                           __________

           To make                              1000 g

Preparation:

Levigate all the solid ingredients in a porcelain dish with about half of the glycerin ( ½  of 788 g) until a smooth mixture is produced. Add the remainder of the glycerin and mix well to make 1000 g. Heat the mixture on a sand bath to a temperature between 15o and 120o with occasional stirring until solution is complete.

Uses: Astringent, useful as local application in sore throat and in mouth sore due to stomatitis. Also it is used to harder nipples to prevent soreness during nursing as a general astringent.

Remarks: The sodium citrate in formula is added to prevent the development of an ink-like color in even a minute quantity of iron should be present.