The government should warn physicians and women that cigarette smoking by users of oral contraceptives "markedly increases the risk" of suffering diseases of the heart and blood vessels, a Food and Drug Administration advisory panel told the FDA yesterday.

The Advisory Committee on Obstetrics and Gynecology recommended that the warning be incorporated in a typographically prominet box in the official labeling for doctors.

The proposed text says that the risk of serious cardiovascular side effects occurs "especially in women older than 35" who smoke on the pill. "Women who smoke and who wish to use oral contraceptives should be advised to stop smoking," the draft says.

The committee also recommended that similar language be included in a new brochure for users which is now being put in final form. Doctors and pharmacists would be required to provide the brochure each time a pill prescription is written or refilled. Current users a number an estimated 7 million to 10 million in the United States alone.

Dr. Edwin M. Ortiz, director of the FDA Bureau of Drugs unit responsible for the pill, told a reporter that he expects the agency will approve the recommendation, both as to the physician labeling and the patient brochure.

FDA Commissioner Donald Kennedy, in an interview Wednesday, said that the brochure will be in use "by the end of the year."

The smoking warning will reflect results of three studies completed within the last eight months.

The most recent data came in October from England, where the Royal College of General Practitioners has been evaluating oral contraception in 46,000 women of childbearing age, half of them users and half of them controls - nonusers studied for comparison since 1968.

In a report in the Oct. 8 Lancet, a medical journal published in London, Dr. Valerie Beral said that among nonsmokers, the death rate from circulaltory diseases per 100,000 women per year was 13.8 for pill users - 4.7 times the rate for nonusers. Among smokers, the mortality rate for users was 39.5 - almost triple that for non-smokers on the pill - and 4.4 times that for smokers who didn't take the pill.

The pill/smoking association began to emerge in May 1975, when another British study established a link between the pill and heart attacks.

Five months later, a biostatistician for the foundation-funded, New York based Population Council, Anrudh K. Jain, told a reporter that a tentative analysis of the British data showed the heart-attack risk to be especially high in smokers.

In a final analysis last March, he drew these key conclusions from the 1975 data:

In the 40.44, age range, the rate of fatal heart attacks per 100,000 women per year is 10.7 among pill users who don't smoke, compared with 62 among pill users who smoke. The rate for women in the same age group who neither smoke nor take the pill is 7.4, compared with 15.9 for smokers who don't use oral contraceptives.

Pill-users in their 40s who are heavy smokers - more than 15 cigarettes a day - suffer fatal heart attacks at a rate nearly 12 times higher than similar women who neither smoke nor use the pill. The rate for the heavy smokers is 83 per 100,000.