Paraffins

Hard paraffin

Hard paraffin is a mixture of solid hydrocarbons, also known as paraffin wax. It is used to stiffen ointments and creams and to coat capsules and tablets. At one time it was used for cosmetic enhancement, for example of the breasts, before silicone was introduced. It is also used in bismuth iodoform paraffin paste (BIPP) (see the monograph on Bismuth).

Soft paraffins

White soft paraffin and yellow soft paraffin are mixtures of semi-solid hydrocarbons. They are used as bases for ointments, as emollients in skin diseases, and as lubricants in treating dry eyes. Soft paraffin is also known as petroleum jelly, petrolatum, and Vaseline.

Liquid paraffin

Liquid paraffin is a mixture of liquid hydrocarbons. Its main use has been as a lubricant laxative but it is not recommended, because of its adverse effects. Nevertheless, it continues to be used for this purpose and is reportedly as effective as lactulose [ ]. However, the erstwhile Committee on Safety of Medicines in the UK recommended the following precautions [ ]:

• pack sizes to be limited to 160 ml;

• liquid paraffin to be used only for the symptomatic relief of constipation;

• prolonged use to be avoided and the package label to state “repeated use is not recommended”;

• to be contraindicated in children under 3 years of age.

Liquid paraffin has also been used in ointments, as an emollient in skin diseases, and as a lubricant in treating dry eyes. Injection of liquid paraffin into the pleural cavity (oleothorax) was a widely used treatment for pulmonary tuberculosis before effective antituberculosis drugs became available. Long-term complications continue to be reported [ ].