Q. Can douching prevent pregnancy and venereal disease? I was told when I was growing up that you should douche right after intercourse. This is not always convenient, but I try to do so for health reasons. Is it necessary?
A. Douching does not prevent pregnancy or sexually transmitted infections. In fact, douching may actually increase the risk of a pregnancy in the fallopian tubes (ectopic pregnancy). This complication can be life threatening.
Gynecologists now believe that douching should generally be avoided. Barrier contraceptives such as condoms are more effective against both pregnancy and sexually transmitted disease.
Q. My thyroid levels jump up and down; sometimes they are too high and other times they’re too low. My doctor is frustrated, but doesn’t seem to know what to do. My tests don’t always coincide with my symptoms. My last test, for instance, came out within the normal range but I have a number of troublesome symptoms: chronic tiredness, dry skin, depression, weight gain, broken nails, and short-term memory loss. I also freeze whenever the air conditioning is on, but if I’m comfortable, everyone else is too warm.
I think I recall reading that Synthroid or Levoxyl may interact with other medications like Prempro or calcium supplements. I take both of those, but don’t remember what the interactions are. Could you please send me information about thyroid tests, treatments and interactions?
A. Minerals like iron and calcium can interfere with the absorption of levothyroxine (Synthroid, Levoxyl, Levothroid, Unithroid). We suggest you wait at least two hours after taking your thyroid hormone before taking mineral supplements. If you are currently taking them at the same time, that might explain your symptoms of low thyroid function.
Estrogen, found in Premarin, Prempro and other hormone replacement formulations as well as in many birth control pills, does not interfere with the absorption of thyroid hormones. But it can alter results of a thyroid test.
We are sending you our Guide to Thyroid Hormones, which tells you about symptoms of thyroid imbalance, interpreting thyroid tests, and medications that can interact with levothyroxine. Anyone who would like a copy, please send $2 in check or money order with a long (no. 10) stamped, self-addressed envelope: Graedons’ People’s Pharmacy, No. T-4, P. O. Box 52027, Durham, NC 27717-2027.
Q. My doctor has told me to take 800 IU of vitamin D daily along with my calcium unless I am getting at least 15 minutes of sun exposure. (I live in Houston, TX, land of strong sun.) My multivitamin contains 400 IU and I take an additional 400 IU supplement.
I have found three forms of vitamin D supplement: tablets, capsules, and softgels. Does it make any difference which one I take? Can I just buy the cheapest ones?
Also, if I am outside but wearing sunscreen, does my skin still make vitamin D?
A. The skin normally makes vitamin D upon exposure to sunlight, but sunscreen impairs this action. Your doctor’s recommendations regarding sun exposure and dose adhere to the latest guidelines.
It shouldn’t make any difference whether you take vitamin D as a tablet, capsule or softgel. This nutrient is critical for bone strength, but research indicates it may also have important anti-cancer properties.