IFAN OFFICE CLINIC was dispensing an awful lot of aspirin and the boss asked why, several problems might be found. One nurse could be handing out the pills casually; some employees might be malingering; pressures in one shop could be causing a rash of headaches, and the clinic might be nursing along some illnesses that need stronger medicine.

That is analogous to what a House panel has learned in its probe of federal agencies' handling of vast amounts of overtime pay - about $1.5 billion last year. Some overtime is justifiable.But Rep. Gladys N. Spellman's subcommittee has found rampant abuse, and some possible fraud. In some departments, payroll management seems to have been incredibly lax. HUD has tightened up its systems since 1975, when investigators tricked a computer into issuing a $99,000 paycheck to "Donald Duck." But the Defense Department is still paying out some $400 million in overtime and can't account for much of it.

Besides straightening out their payroll systems, federal managers obviously need to crack down on supervisors who let ordinary work drift into overtime or dispense premium pay as a morale-builder or reward for favored employees. Situations where civil servants do overtime work routinely need attention too. Last year, for instance, about 2,700 immigration inspectors got nearly $15 million in overtime pay. Some of that was unavoidable, but Congress should reassess the 1931 law that sets higher overtime rates for those agents than for other law-enforcement officers. It should also be found out how much the agents' hours could be reduced by better management, not just expansion of the force.

In addition, repeated overtime strains people as well as payrolls. One official described State Department security agents as "well-to-do, but overworked and financially over-extended" because they have come to count on premium pay. That trap can quickly wear good people down. Yet reducing their hours is painful relief if it means slashing their pay. The situation is a sharp reminder that cracking down on abuses is only part of the management challenge being spotlighted by the House inquiry.