Monograph: |
Liquid Paraffin
Liquid paraffin is a mixture of liquid saturated hydrocarbons
obtained from petroleum. The USP permits a suitable stabilis-
er.
It is a transparent, colourless, odourless, or almost odourless,
oily liquid, free, or practically free. from fluorescence by day-
light. Practically Insoluble in water, in ether, and in hydrocar-
bons: practically insoluble to slightly soluble in alcohol:
miscible with fixed oils (except castor oil) and soluble in vol-
atile oils. Store in airtight containers. Protect from light.
Adverse Effects and Precautions
Excessive dosage by mouth, or rectum, may result in anal
seepage and irritation. Liquid paraffin is absorbed to a slight
extent and may give rise to foreign-body granulomatous reac-
tions. Similar reactions have followed the injection of liquid
paraffin and may be considerably delayed in onset. Injection
may also cause vasospasm and prompt surgical removal may
be required to prevent severe damage. Lipoid pneumonia has
been reported following the aspiration of liquid paraffin.
Chronic ingestion of liquid paraffin may rarely be associated
with impaired absorption of fat-soluble vitamins and possibly
other compounds. It should not be used when abdominal pain.
nausea, or vomiting is present. Prolongedβuse should be
avoided. Also it should not be used in children under 3 years
of age.
Haematological changes and deposition of food grade liquid
paraffins in the liver, spleen, and lymph nodes has occurred
during feeding studies in rats.
Uses and Administration
Taken internally, liquid paraffin acts as a lubricant and, since
it keeps the stools soft, it has been used in the symptomatic
treatment of constipation ,although its use is gener-
ally not recommended. Up to 45 mL has been given daily by
mouth, usually in the evening but should not be taken imme-
diately before going to bed. Liquid paraffin is an ingredient of
several preparations that contain other laxatives such as cas-
cara. magnesium hydroxide, or phenolphthalein. It has also
been given as an enema in a usual dose of 120 mL.
Externally, liquid paraffin may be used as an ingredient of
ointment bases, as an emollient and cleanser in certain skin
conditions, and as an ophthalmic lubricant in the management
of dry eye .
Light liquid paraffin has similar uses to liquid paraffin.
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