There is perhaps no drug which has attained such a wide and universal currency for this purpose in the civilized world of today. Its acceptance is based on the belief that mineral oil is a bland and innocuous intestinal lubricant, while the numerous and considerable deleterious effects which may follow its continued administration have failed to be recognized.
In this paper attention will be drawn to the effects of mineral oil in disturbing normal physiologic processes, as well as to the pathologic changes which may attend its use.
The texts on pharmacology suggest no rational therapeutic basis for the use of liquid paraffin, the chemistry of which is, to say the least, uncertain.
The rectum is not a reservoir. Functionally it is but a short passage to the exterior.
The use of mineral oil as a laxative is open to severe criticism on the ground that it destroys the normal physiologic processes.
When mineral oil is present in the rectum complete evacuation is impossible.
The use of mineral oil was shown to be the cause of weight loss in children by Till and Dutcher.
Mineral oil, whether or not it is in complete emulsion, hastens the motility of the bowel contents in the small intestine and, as a consequence, digestion is incomplete.
There is clinical evidence that individuals who have taken oil over a long period of time suffer from “indigestion/’
Mineral oil should never be given before or after operations on the rectum.
The use of mineral oil is often an indirect cause of pruritus ani.
Channon and Collinson proved that oil is absorbed from the gut and that it appeared in the livers of rats and pigs.
A. Physiologic Considerations:
1. Mineral oil lubricates the rectosigmoid and makes a reservoir of the rectum.
2. Mineral oil makes complete evacuation impossible.
3. Mineral oil has a very deleterious effect on the nutritional economy of fat-soluble vitamins.
4. Mineral oil hastens the motility of the bowel contents and thereby prevents complete digestion.
5. Mineral oil may interfere with the process of absorption throughout the bowel.
B. Pathologic Considerations:
1. Mineral oil interferes with the healing of postoperative wounds in the anorectal region and may induce hemorrhage.
2. Mineral oil is often the indirect cause of pruritus ani.
3. Evidence is accumulating that mineral oil may be absorbed, producing pathologic changes in the liver and other abdominal viscera.
The internal administration of mineral oil, either alone or in combination with other substances, may be attended by decided disadvantages. In view of the light-heartedness with which mineral oil has been prescribed as a laxative, I feel that this discussion is timely.
James W. Morgan, M.D. San Francisco (1938, California And Western Medicine)