Synthroid

Synthroid may cause seizures at the beginning of treatment, although this is rare. You may also notice some hair loss at first, but this is temporary.

It may take a few weeks for Synthroid to begin working, and you may not see any change in your symptoms until then.

Tell your doctor or dentist you are taking Synthroid before you have surgery of any kind.

Tell your doctor if you become pregnant while you are taking Synthroid. Your dose may need to be increased.

Do not switch to another brand of levothyroxine without consulting your doctor.

Excessive doses of Synthroid in infants may cause the top of the skull to close too early. In children, overtreatment can stunt growth.

Possible food and drug interactions when taking Synthroid

Synthroid can interact with a wide variety of medications. It's advisable to check with your doctor before taking any other drug, but you should be especially wary of the following:

Amiodarone (Cordarone)
Androgens (male hormones)
Antacids and anti-gas medications
Antidepressants such as Elavil, Ludiomil, and Zoloft
Blood pressure drugs such as beta blockers, nitroprusside, and thiazide diuretics
Blood-thinning drugs such as Coumadin and heparin
Chloral hydrate (a sedative)
Diabetes drugs such as insulin and Micronase
Digitalis-type drugs such as Lanoxin
Estrogen products and oral contraceptives
Furosemide (Lasix)
Growth hormones
Hormone inhibitors such as Cytadren and Tapazole
Iodide
Iron supplements
Kayexalate
Ketamine (Ketalar)
Lithium (Eskalith, Lithobid)
Methadone and heroin
Metoclopramide (Reglan)
Nonsteroidal anti-inflammatory drugs such as phenylbutazone and aspirin
Parkinson's drugs such as Sinemet
Propylthiouracil (a thyroid inhibitor)
Seizure medications such as Dilantin, Tegretol, and phenobarbital
Steroids such as dexamethasone and hydrocortisone
Stimulants such as epinephrine (EpiPen)
Sucralfate (Carafate)
The cancer drugs 5-fluorouracil, 6-mercaptopurine, mitotane, and tamoxifen
The cholesterol-lowering drugs Colestid, Mevacor, and Questran
The immune-system drugs interferon and interleukin
The tranquilizers Trilafon and Valium
The tuberculosis drugs aminosalicylate, rifampin, and ethionamide
Theophylline (Theo-Dur)

A high-fiber diet, soy-containing supplements, and walnuts can also interfere with Synthroid effects.