for those taking synthroid, levothyroxine, etc

[artteacher]

I thought you might be interested in this information on foods and rx's that will interfere with your medicine:

Jo Prang - Medicap PharmacyCenter:

You asked if there is a complete of foods, vitamins, supplements, and medications that interact with Synthroid. Although, there is never a complete list of any medication, there is an extensive one for Synthroid.
Synthroid interacts with the following items:

Alfalfa- may cause a flare or increase of thyroid hormone. Should not be used in combination with Synthroid.

Aluminum hydroxide- antacids containing aluminum are the big culprits. The aluminum binds to the Synthroid in the GI tract and interferes with the absorption of the hormone. Taking the medications at different times cannot prevent this interaction. It is suggested that all aluminum products be discontinued.

Amiodarone- has a complex effect on thyroid hormones and can alter thyroid function tests.

Tricyclic antidepressants (amoxapine, imipramine, etc…) – may enhance the effects of the Synthroid and could cause heart toxicity.

Antidiabetic agents- may require an increase in Synthroid dosage.

Antithyroid agents- they have opposing effects and should not be used together.

Barbiturates- could cause a decreased response to thyroid hormones if used in combination.

Betel Nut- may alter thyroid hormone levels.

Beta-blockers- (Toprol XL, Coreg, etc…) Synthroid may cause cardiac stimulation and increase the heart rate. The effects of beta-blockers may be reduced.


Bladderwrack contains variable levels of iodine (up to 600 micrograms of iodine per gram of bladderwrack). As a result, it has been used to treat thyroid disorders such as goiter. Although there are case reports of seaweed/kelp products causing hyperthyroidism, there have not been studies of dosing, safety, or efficacy, and there is no widely accepted standardization of iodine content for these products. While the evidence does suggest thyroid activity, there is not enough research to support this use of bladderwrack.
Calcium Carbonate and other calcium salts- lead to decreased absorption. To avoid interaction, administer Synthroid at least 4hours before or after calcium supplements.

Carbamazepine- may cause decreased response to Synthroid.

Chaparal- may aggravate hypothyroidism.

Cholestyramine and colestipol- decrease the absorption of Synthroid. To avoid interaction, administer Synthroid at least 4hours before or after cholestyramine or colestipol.

Corticosteroids- may alter thyroid hormone levels.

CoenzymeQ10- may alter levels of thyroid hormone.

Cytokines (interferon, interleukin): Cytokines have been reported to induce both hypothyroidism and hyperthyroidism

Dantrolene- may alter thyroid hormone levels.

DHEA- may alter levels of thyroid hormone.

Didanosine- decreases the absorption of Synthroid. To avoid interaction, administer Synthroid at least 4hours before or after didanosine.

Digoxin- the clearance of digoxin is decreased with the concomitant use of Synthroid.

Enteral feedings (tube feedings, ensure, boost, etc…)- can inhibit the absorption of Synthroid. To minimize the risk of an interaction, thyroid hormones should be administered on an empty stomach at least 30 minutes prior to food or enteral feedings. Foods that may decrease thyroid hormone absorption include soybean flour, and soy based infant formulas or enteral feedings. High fiber diets, cottonseed meal and walnuts can also have a similar effect.

Estramustine- may alter thyroid hormone levels.

Estrogen (Premarin, Prempro, birth control pill, etc…) the administration of estrogens and oral contraceptives can decrease the response of Synthroid.

Flaxseed- may affect the coagulation properties of the body.

Follitropin alfa- may alter thyroid hormone levels.

Garlic- may decrease thyroid hormone levels.

Horehound- may increase heart rate and drop blood pressure with concomitant use.

Indinavir- may decrease the absorption of Synthroid.

Iodoquinol- may alter thyroid hormone levels.

Iron- may decrease the absorption of Synthroid. To avoid interaction, administer Synthroid at least 4hours before or after iron containing supplements.

Ketamine- concomitant use may lead to increased heart rate and blood pressure.

Leuprolide- may alter levels of thyroid hormone.

Lutropin alfa- may alter levels of thyroid hormone.

Mecasermin- may alter thyroid hormone levels.

Melatonin- may alter thyroid levels.

Menotropins- may alter thyroid hormone levels.

Mercaptopurine- may alter thyroid hormone levels.

Niacin- may decrease the level of thyroid hormone.

Peginterferon alfa-2b- may alter thyroid hormone levels.

Phosphorous supplementation- may worsen hypothyroidism.

Probenicid or Colchicine- may alter thyroid hormone levels.

Raloxifene- may decrease the absorption of Synthroid.

Rifampin- may decrease the response of Synthroid.

Rivagistamine- may cause seizures in poorly controlled individuals.

Selenium- may increase the levels of thyroid hormone.

Sevelamer- may decrease the absorption of Synthroid. To avoid interaction, administer Synthroid at least 4hours before or after sevelamer.

Soy- may decrease thyroid hormone levels.

St. John’s Wart- may increase thyroid-stimulating hormone.

Sulfapyridine- may lower thyroid levels.

Terbinafine- may alter thyroid hormone levels.

Kayexalate- may decrease the absorption of Synthroid. To avoid interaction, administer Synthroid at least 4 hours before or after kayexalate.

Sucralfate- may decrease the absorption of Synthroid. To avoid interaction, administer Synthroid at least 4 hours before or after sucralfate.

Theophylline- may decrease the clearance of theophylline.

Warfarin (coumadin)- concomitant use of coumadin and Synthroid may enhance the effects of coumadin and increase anticoagulation. PT/INR should be monitored closely.


Medications that may have a stimulating effect on the body should be avoided. These medications may be found in over the counter cold and cough medications. Sudafed may increase the heart rate and blood pressure, adding to the effect of hyperthyroidism.

Although this is not a complete list, it does give you an idea of how much your thyroid plays in your health and everyday life. I could not find any interactions between your grape seed extract and Synthroid. It sounds as if you are very cautious and conscientious of your health. I wish you the best of luck and please don’t let this list intimidate you.

Sincerely,
Jo Prang R.Ph

If anyone wants the link to this site (about thyroid and other hormones) let me know.

Merry Christmas, Marsha

[barbaranoela]

not so surprising to read---

WHEN one reads all the *bewares* of other meds.---interaction and etc.--makes U wonder if one should be taken what one does!!!


thanks Marsha----

PS. let me know how ya hubby is???

[artteacher]

Hi again,

He's actually not so hot. His mystery disease (chronic fatigue or something) is flaring again, so he's always tired. And he's taking medicine for gastric reflux and eroded esophogus that gives him a really upset stomach and bad dreams. Every morning is entertaining, though, when he tells about his weird dreams. Last night he was selling used car parts in his sleep.

As you know, it's always something. Love, Marsha