Thyroid Overmedication: What Are The Signs?

The thyroid is a small gland on the front of the neck, just below Adam’s apple for men. It produces two main hormones, triiodothyronine (T3) and thyroxine (T4).  Among other functions, they regulate the body’s metabolism.

Thyroid disorders often cause the over- or underproduction of these hormones. The overproduction of hormones is called hyperthyroidism, and the underproduction is called hypothyroidism. 

Prescribing medications is a common therapeutic approach in both conditions. However, overmedication is more frequent in managing hypothyroidism, in which a synthetic thyroxine triiodothyronine is given. 

The most common medication for thyroid hormone replacement is levothyroxine sodium, a synthetic copy of thyroxine. Another medication, liothyronine, is a synthetic version of triiodothyronine. 

There are many synthetic hormone replacements available. The most important thing to get right is the dose, as these hormones in excess could be detrimental to your health. 

Your doctor should monitor your hormone levels intermittently to determine the appropriate dose, which you will then take daily, usually for the rest of your life. 

How thyroid medication treats hypothyroidism

Medication for hypothyroidism aims to replace the hormone that the thyroid can’t produce. 

Hypothyroidism can be caused by an autoimmune disorder, surgical removal of the thyroid, or as a side effect of radioactive iodine treatment. These medications relieve the symptoms by providing you with the right amount of thyroid hormone. 

What medication treats hypothyroidism?

Several medications treat hypothyroidism. Most of them are synthetic versions of the hormones your thyroid would produce naturally. They include:

• Levothyroxine sodium

• Liothyronine

• Liotrix

• Natural thyroid

Levothyroxine sodium is a synthetic version of thyroxine, while liothyronine is a synthetic version of triiodothyronine. Liotrix is a combination of synthetic versions of both. 

Natural thyroid medication is made up of desiccated animal thyroid and was used before synthetic hormones were created. Some people still prefer to take this over synthetic ones. 

What causes thyroid overmedication?

There are many possible reasons why you could be overmedicated. First, it is difficult for doctors to prescribe the right dose immediately, and the process can involve trial and error. 

The prescribed dose also depends on blood hormone concentrations. Doctors usually adjust it after analyzing the results of blood tests. However, no organism is the same as another, and the response to treatment can vary, causing the doctor to adjust the dose of the drug in some cases.

Here are two other reasons for overmedication:

Dose or drug quality issues

The dose of your medication could be wrong due to quality or prescription issues. Sometimes, slight changes in the medication potency can cause an upsurge in thyroid hormone in your body. 

This can sometimes happen between prescriptions, as some batches of the drug can have very minute differences. Because the balance of hormones in your body is so delicate, these differences can add up. 

Sometimes, switching between different forms of medication can also change how well your body absorbs it. For example, a tablet form versus a liquid form of a drug may have different absorption rates. Your hormone levels should be monitored regularly and more frequently at the beginning of the treatment.

Change in diet

A change in diet can sometimes adversely affect a medication’s action. This is because the food you eat can change how you absorb the medication. For example, switching to a less fibrous diet can affect how your body absorbs the drug.  

Supplements containing too much iodine may also contribute, as iodine is a crucial nutrient that the thyroid uses to make hormones. Consuming excess iodine can cause excess production of thyroid hormones. 

If you have made a sudden change to your diet that you wish to continue, you may need to consult your doctor to raise or lower your dose of thyroid medication.

Signs and symptoms of overmedication

Signs and symptoms of overmedication can vary with the condition it creates.

The hormones the thyroid makes are used all over the body and affect how it uses energy. Often, the symptoms of overmedication can be mistaken for other diseases.

Symptoms of overmedication in hypothyroidism management are the same as hyperthyroidism, such as:¹

• Anxiousness

• Focusing difficulties

• Exhaustion

• More frequent bowel movements

• Feeling unusually hot

• Hunger

• Tremors

• Loss of hair

• Sweating

• Nerves

• Difficulty sleeping

• Weight loss

• Restlessness

• Goiter (growth on the thyroid)

• Heart palpitations

You may experience only a few of these symptoms. However, it is better to speak to a doctor as soon as you notice a change in your health. Allowing the disease to continue untreated could have progressively damaging effects. 

Signs your thyroid medication is working

You will know your thyroid medication is working if your symptoms decrease. You may experience more energy or an overall better quality of life. 

This lessening of symptoms should not be accompanied by new ones. It should take only days to see improvement. However, your hormone levels may take months to level out fully.

Thyroid medication withdrawal symptoms

Withdrawal symptoms of thyroid hormone replacements usually mimic the symptoms of the condition before treatment starts. These could include:

• Low energy levels

• Weight gain

• Constipation

• Hair loss

• Dry skin

• Pain in joints and muscles

• Depressive symptoms

• Increased sensitivity to cold 

• Slowed speech

• Low physical growth

• Anxiety

• Insulin resistance

• Brittle nails

Do not stop using your thyroid medication without consulting a medical professional. They can decide if this process is necessary and, if so, guide you through the withdrawal. 

Most patients stay on hormone replacements for life. In some cases, patients with thyroid cancer may need to lower their dose before appointments and can experience withdrawal symptoms.

Monitoring for overmedication

A huge part of treatment for an underactive thyroid is monitoring thyroid hormone levels regularly. Your doctor will keep track of your levels of triiodothyronine and thyroxine. 

This will involve regular blood tests and checkups with your doctor. Therefore, overmedication can be detected quickly and accurately even if you do not notice symptoms. 

The lowdown

Overmedication is a daunting thought. However, there is no need for concern. Your medical professional will guide you as smoothly as possible through the transition into treatment. 

If you have continuing symptoms after beginning treatment or develop new ones, such as anxiousness, exhaustion, restlessness, hair loss, or any of the others listed under the symptoms section, you may want to consult your doctor. 

It is better to get any excess medication under control since overmedication can cause hyperthyroidism. If it is not a dose issue, your doctor may discuss how you can optimize your diet or the dosage to minimize your symptoms as much as possible. 

There are multiple ways of treating hypothyroidism. It is simply a process of finding what works best for you. 

Frequently asked questions

What are the signs and symptoms of overmedication with levothyroxine?

Signs of being overmedicated on levothyroxine are similar to hyperthyroidism. These include:

• Irritability

• Weight loss

• High blood pressure

• Fast heart rate

• Anxiety

• Frequent bowel movements

• Exhaustion

• Difficult sleeping

• Susceptibility to heat

What is the recommended dose for levothyroxine?

Thyroid diseases are very variable, and treatment often depends on many factors. This means there is no set dose for adults with hypothyroidism. Your doctor will work with you to find the appropriate dose.

How do you treat thyroid overmedication?

You treat thyroid overmedication by adjusting the dose, diet, or other factors that affect how your body absorbs the medication. 

What are the early warning signs of thyroid problems?

There are a few early warning signs of hypothyroidism. These are often hard to detect as they could be attributed to several other diseases. Some symptoms include:

• Constipation

• Dry skin

• Change in the way you react to temperature

• Fatigue

• Hoarseness

• Hair loss

• Weight gain 

• Mood swings

Will I be on thyroid medication forever?

Unfortunately, underactive thyroids cannot be cured. Patients will usually have to remain on medication for the rest of their lives. 

Treatment will likely consist of a daily dose provided specifically for your body’s needs. The dose can be adjusted if more or less hormone replacement is required.

What happens if you don’t take thyroid medication?

If you do not take your thyroid medication, your symptoms will return and progress. This can create more severe health problems the longer the disease is left untreated. Complications could include nodules forming on the thyroid or myxedema crisis.²