THERE IS a grating dissonance between HEW Secretary Joseph Califano's fervently expressed concerns about the dangers and wastefulness of some present day medical practices and his tepid response to the growing weight of evidence against the popular painkiller Darvon.

One of the most widely prescribed pharmaceutical drugs, Darvon has been indicted by expert medical authorities on two interconnected grounds: First, contrary to the promotional claims of its principal manufacturer, Eli Lilly & Co., it is relatively ineffective as a painkiller, a fact that often lures unsuspecting patients to exceed the recommended dosages; second, taken in excess, or in combination with alcohol or tranquilizers, Darvon can be seriously disabling -- or lethal.

Data collected from the one-third of the country covered by the Drug Enforcement Administration's Drug Abuse Warning Network linked the compound -- chemically known as propoxyphene -- to 607 deaths in 1977. Chicago's Cook County Hospital banned use of the drug 18 months ago because, as its chief of medicine has stated, Darvon was found to be costlier than and inferior to common aspirin and "the object of dangerous abuse by growing numbers of people...." The chief coroner of San Francisco has concluded that "because of its frequency of abuse and because of its propensity for toxic results in relatively low doses when mixed with other compounds, such as alcohol, the position of this office is that propoxyphene should be withdrawn from the market."

A petition calling for such a ban, or at least for severe restrictions on prescribing the drug and refilling prescriptions for it, was submitted last November by the Health Research Group, the medical arm of Ralph Nader's Public Citizen organization. Mr. Califano's response, which strikes us as both disappointing and inexplicable, came last week: He's going to study whether Darvon ought to be restricted, with a decision due in June; in the meantime, HEW will be warning physicians and other health professionals about the reported dangers of the drug, which Mr. Califano acknowledges to be associated with "more deaths than... any other prescription drug."

We might be able to sympathize with Mr. Califano's cautious approach if Darvon were an indispensable drug for life-saving or pain-alleviating purposes. But it is nothing of the sort, as a Senate inquiry was recently told by Dr. Charles G. Moertel of the Mayo Clinic, who said that, on the basis of his own research and an extensive review of the medical literature, "I would seriously question whether the use of Darvon is good medical practice at all."

We might also share Mr. Califano's preference for caution if reports about the dangers of Darvon were few, fresh and unevaluated. But, as a matter of fact, the data have been accumulating for at least four or five years -- with the total reported death count in excess of 2,000. As long ago as 1973, a senior government health official warned that the drug has the characteristics of restricted narcotics and should be treated accordingly.

Since Mr. Califano has declined to employ his authority to sweep Darvon off the market by declaring it an "imminent hazard," we hope that in tandem with the Justice Department -- which has jurisdiction over so-called controlled substances -- he will expedite the process of restricting its availability.

There is no reason why this dubiously useful, often dangerous drug should be eligible for multiple refills or easily abused telephoned prescriptions. For those physicians and patients who find it desirable, Darvon would still be available under restricted circumstances. The important point is that Darvon can be perilous and ought to be treated as such.