Oral hypoglycemic agent update.
The treatment of diabetes is still a problem more than a half-century after the discovery of insulin. Patients are now living significantly longer but until the development of oral hypoglycemic agents, the only direct treatment modalities were exercise, diet, and insulin. Before evaluating the effectiveness of treatment, a therapeutic goal must be determined. While there are no absolutely "hard" facts proving that "good control" is beneficial in preventing chronic complications of diabetes, increasing accumulation of "soft" data strongly suggests that normal blood glucose levels are most desirable, when possible, but not at the cost of severe or disabling hypoglycemic reactions. The development of the oral agents was a great public health advance in that many persons with early diabetes, but fearful of insulin injections, had less dread of "the pills" and sought treatment. The oral agents simplified care but this very simplification process often undermined the need for proper diet and good fundamental care. This often led to mediocre diabetes care. While useful, the oral agents have marked limitations and in some are effective only temporarily. The presently available oral agents are sulfonylureas and require a viable beta-cell system for success. This limits the number of diabetics responsive to such treatment. The general indications for tolbutamide, chlorpropamide, acetohexamide and tolazamide are in maturity-onset diabetics, generally beyond the age of 40 with diabetes of less than 10 years. They are contraindicated in juvenile-onset diabetics, in pregnant women, and usually in patients undergoing major surgery, and can become ineffective during periods of extreme stress or during severe infection. They can lower blood glucose levels if used in proper doses in properly selected patients. Contrary to several decades of documentation, it has become popular to suggest that the oral agents are not effective. They can be effective but for many reasons apparently were not in their use by the U.G.D.P. researchers. This might not be the fault of the oral agent used. If ineffective, they should be discontinued. Many, but not all, patients may respond to diet therapy, which is then the treatment of choice. Obviously insulin, though difficult to use for many persons and in itself able to induce several severe reactions if not used properly, is the only treatment (with diet) for the severe diabetic. There is a large spectrum of patients inbetween in whom the oral agents may be useful. The use of phenformin (phenethyl-biguanide) has been effectively curtailed because of many reported cases of lactic acidosis, and while it is doubtful that phenformin alone, in the absence of complicating factors, is the causative factor, it is capable of being an augmenting influence when other conditions, such as decreased kidney function, prevail...