Dear Dr. Gott:<$> I am a 53-year-old wife and mother with a question. I have read that after one year without having a period, I do not have to be concerned about birth control anymore. How exact is that? At what time can I be absolutely sure that I do not need to use birth control of any kind? I have never had a permanent form of sterilisation performed and am anxiously awaiting the day when I have no need for any birth control.

Reply: The traditional thinking is that once a woman enters menopause and stops having monthly bleeding for a year, she cannot become pregnant. This is, of course, a general statement and is not a guarantee of infertility. If you want to stop birth-control medication, check with your gynaecologist first. To give you related information, I am sending you a copy of my Health Report “Contraception — An Update”. Other readers should send a long, self-addressed, stamped envelope and $2 to Newsletter, PO Box 167, Wickliffe, Ohio 44092.

Dear Dr. Gott: I am amused by your declaration that you will buy into “alternative” health practices only after they are analysed as meticulously as new pharmaceuticals — and yet you advocate Vicks VapoRub for fungus and soap under the sheet for leg cramps “because they work”. Huh?

Reply: Using a bland and safe topical product does not affect a person’s health the way standard pharmaceuticals may. I insist on the appropriateness of testing oral and injectable drugs and pills, but such testing is not necessary for Vicks and soap, both of which appear to have benefits in certain circumstances.

Dear Dr. Gott: I just read your column in response to workplace drug testing, in which you advocated an employee’s right to appeal a “false positive” test. I deal with this testing on a daily basis, and I can only emphasise that this issue serves to reinforce how important it is to have drug testing performed by federally certified laboratories, and have the employer’s programme overseen by a medical-review officer. The federal labs operate under strictly legislated quality controls. The medical-review officer reviews all positive tests and, before reporting the results, he or she interviews the employee to determine if a legitimate prescription medication or other substance could have caused the positive test. By reviewing the type and amount of various metabolites present, or ordering additional testing, it is possible to tell the difference between a poppy-seed roll and a legal painkiller. Lastly, since I have seen this in your column before, nothing but marijuana tests positive for marijuana. The tests are not either positive or negative. They are specific for certain drugs and are verified by a second test, which identifies the chemical signature of each molecule. It is even possible to distinguish between the two mirror images of the same molecule, which can make the difference between legal and illegal.

Reply: Thank you.