Overview, Advantage And Disadvantage Of Pharmaceutical Lotion

A lotion is a low-to medium-viscosity medicated or non medicated topical preparation, intended for application to unbroken skin without friction. Lotions are usually applied to external skin with bare hands, a clean cloth, cotton wool, or gauze. The insoluble matter should be finely divided as particles approaching colloidal dimensions are more soothing to inflamed areas and are more effective in contact with infected surfaces and devoid of grittiness. A wide variety of ingredients may be added to the preparation to produce better dispersion or to accentuate the cooling, soothing, drying, or protective properties of the lotion.

Lotion

Most lotions are o/w emulsions, but w/o lotions are also formulated. The key components of a lotion are the aqueous and oily phases, an emulsifying agent to prevent separation of these two phases, and, if used, the drug substance or substances. A wide variety of other ingredients such as fragrances, glycerol, petroleum jelly, dyes, preservatives, and stabilizing agents are commonly added to lotions for improved organoleptic and preservation characteristics.

Read Also: Types of pharmaceutical liquid

Lotions can be used for the topical delivery of medications such as antibiotics, antiseptics, antifungals, corticosteroids, anti acne agents, and soothing/protective agents (such as calamine). Aside from medical use and skin care, lotions are often used as accessories to aid massage, masturba-tion, or sex. Non Comedogenic lotions, products that do not block the natural pores of the skin, are recommended for use on pimples or acne-prone skin. These lotions are also termed as nonocclusive. Thus, they may reduce acne and/or reduce the incidence of pimples.

The same drug substance can be formulated into a lotion, cream, and ointment. Lotion is less viscous and may be readily applied to these hairy parts like the scalp. Many medicated shampoos are, in fact, lotions. Lotions also have an advantage that they may be spread thinly compared to a cream or ointment and may economically cover a larger area of skin.

All topical products, including lotions, can result in the percutaneous (through the skin) absorption of their ingredients. Absorption through the skin is increased when lotions are applied and then covered with an occlusive layer, when they are applied to large areas of the body, or when they are applied to damaged or broken skin. Lotions are ideal for everyday wear, especially if you have typical to oily skin. These products absorb quickly into the skin without any residue. 

Preparation Of Lotion

Lotions are usually liquid suspensions or dispersions intended for external application to the body. They may be prepared by:

(1) Triturating the ingredients to a smooth paste and then cautiously adding the remaining liquid phase or in larger quantities by the use of high-speed mixers or homogenizers.

(2) By chemical interaction in the liquid. 

Manufacturing lotions and creams can be completed in two cycles:

1. Emollients and lubricants are dispersed in oil with blending and thickening agents

2. Perfume, color and preservatives are dispersed in the water cycle

Active ingredients are broken up in both cycles depending on the raw materials involved and the desired properties of the lotion or cream.

Read Also: All about pharmaceutical emulsion

A typical oil-in-water manufacturing process may be:

Step 1: Add flake/powder ingredients to the oil being used to prepare the oil phase

Step 2: Disperse active ingredients

Step 3: Prepare the water phase containing emulsifiers and stabilizers

Step 4: Mix the oil and water to form an emulsion. (Note: This is aided by heating to between 110-185 F (45-85 C) depending on the formulation and viscosity desired.)

Step 5: Continue mixing until the end product is 'completed'

Advantages Of Lotion

1. Penetrates skin easily

2. Leaves minimal residue

3. Lotions contain Alcohol that provides drying effect

4. Least greasy and occlusive of all preparation bases

Disadvantages Of Lotion

1. Least potent vehicle for medication delivery