Not All Thyroid Medications Are Equal

Are you taking thyroid medication and still suffering with symptoms? Which thyroid medication are you on? Many patients are surprised to learn that thyroid medications are not created equal.

In the world of prescription medication, most drugs to treat a disease are very similar and the choice typically comes down to cost with many patients choosing generic medication for the exceptional cost differences. However, thyroid medication is a case where the benefits of a brand name outweigh the cost differences.

What thyroid medications are out there? The most widely prescribed medication is the synthetic hormone (e.g. Synthroid and the generic levothyroxine). Another popular medication is the natural hormone replacement, Armour. (A quick online search will explain how the synthetic and natural medications work.)

The most dramatic difference in the medications is surprisingly not between the synthetic and natural medications, although many patients do notice a difference after switching to the natural form. In the case of thyroid medication, the brand name (e.g. Synthroid) is superior to the generic (e.g. levothyroxine). In fact, the FDA does not regulate the generic form as closely and the strength of the pills can vary as much as twenty percent from the dosage level. For example, if a patient is prescribed 100 mcq of levothyroxine, the strength of one pill may be 80 mcq and another pill may be 120 mcq, all in the form of a 100 mcq pill.

Why is this difference a problem? To answer this question, a quick explanation of what happens when a patient is diagnosed with a thyroid condition is necessary. Typically, blood tests will reveal that a patient is suffering from thyroid problems. A patient who is hypothyroid has a higher TSH number. The TSH is the amount of thyroid stimulating hormone circulating through the body. Based on the initial TSH and the patient's physical makeup, the physician prescribes a daily dosage of thyroid medication, such as 100 mcq. When the patient takes the thyroid medication, the missing thyroid hormone is replaced and the TSH number is lowered. Ideally, within six weeks of beginning treatment, the TSH blood test should be within the normal range (.3 - 3.0). If not, the dosage is adjusted and the TSH is retested in four to six weeks.

However, if a patient is taking the generic levothyroxine, sometimes stabilization is not achieved possibly due to the varying strengths of the individual pills. If a patient is taking levothyroxine and still experiencing symptoms or a TSH outside of the normal range, serious consideration should be given to switching to the brand name or natural medication. In this situation, having a physician who truly understands thyroid disease and thyroid medication is extremely important. Without the understanding, a physician may attribute the symptoms to another source and prescribe unnecessary medication.

Personally, when I was diagnosed with hypothyroidism, I was prescribed levothyroxine. For eighteen months, I struggled with the bone-numbing fatigue, dry skin, brain fog, and a host of other symptoms. I knew, based on my body's symptoms, if my TSH was stable. Typically, it was not. For almost a year, I had my TSH tested every month and was prescribed six different strengths of levothyroxine. At one point, my physician attempted to give me depression medication and failed to understand that the mood swings were related to the thyroid and no amount of depression medication would help because the root problem still existed. I requested a switch to the brand name, but her opinion was that the levothyroxine was the most prescribed form and was sufficient. After that appointment, I was able to have a follow-up with another physician in the same practice, and immediately after reviewing my past history and TSH levels, he suggested changing to the brand name. His opinion was that if a patient doesn't stabilize within six months on the generic, the generic would not work. Later when I dropped off the prescription at a local pharmacy, the pharmacist commented that for the majority of drugs, the generic is the equivalent and sometimes superior to the brand name, however for thyroid medications, that wasn't the case.

Ideally, when thyroid medication is correctly treating the problem, the patient should experience very limited to no symptoms of thyroid disease.

The information contained in this article is based on common knowledge as well as personal experience. The author is not a physician, but is a thyroid patient. Before making any medical conditions, please consult with your physician.