Levothyroxine Makes Me Feel Awful – What To Do If Thyroid Medication Isn’t Working?

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Taking levothyroxine can take some time to make you feel better and show its effect. Initially, it might make you feel unsettled or weird, and you could experience mild side effects. But in about two months, the medication should take effect. Reasons for feeling awful could also include not getting enough dosage, your body producing too much thyroid, and facing conditions such as depression or anemia. Don’t switch your medicine or stop taking it and focus on the correct dosage at the right time of the day. If you still feel awful after some time, it’s best to let your doctor know, for they might change your dosage or even refer another medicine. 

For people who suffer from hypothyroidism, taking levothyroxine is one of the medications that are recommended. Those suffering from this condition suffer from slow metabolism as the thyroid gland doesn’t make enough thyroid hormone.

Taking levothyroxine is supposed to work as a thyroid hormone treatment by replacing the thyroxine that your body isn’t producing in adequate amounts. 

Taking this medication is supposed to regulate your energy production, amongst other things, but if it’s making you feel awful, there’s a need to reflect.

How does hypothyroidism make you feel?

The symptoms of hypothyroidism might differ from person to person. While someone might feel, more tired other people could gain weight easily, or even a combination of both.

In the beginning, it’s difficult to discern the problem, but here are the symptoms to watch out for:

  • Tiredness
  • More sensitivity to cold
  • Constipation
  • Dry skin
  • Weight gain
  • Puffy face
  • Hoarse voice
  • Coarse hair and skin
  • Muscle weakness
  • Muscle aches, tenderness, and stiffness
  • Menstrual cycles that are heavier than usual or irregular 
  • Thinning hair
  • Slowed heart rate
  • Depression
  • Memory problems

How does taking levothyroxine helps the thyroid?

Since the body isn’t producing enough thyroxine, which regulates energy and growth, administering this medication is supposed to act on behalf of this hormone and regulate your body to reduce tiredness, weight gain, muscle weakness, depression, and dry skin. 

But not each person’s body is suited to this medication. While some might feel right by taking it, others could feel awful or low on energy.

Why do I feel awful on levothyroxine?

A woman is sitting down because she's starting to feel awful after taking her thyroid medicine
  • There could be a dosage issue where you’re not getting enough for your body’s requirements.
  • Your thyroid could also produce too much thyroid hormone (hyperthyroidism), which can cause tiredness.
  • You could be facing other conditions that are causing the tiredness, such as depression or anemia, apart from a thyroid disorder. 

What to do if your thyroid medication isn’t working?

If your thyroid medication isn’t working the way it’s supposed to, one way to test it is by getting TSH done every few weeks in the beginning. 

Under medication or overmedication can both be problematic. If you’re not getting enough of the hormone, you could feel similar issues before taking the medication and finding out nothing has gotten solved. 

While taking too much of this hormone treatment could lead to feeling hot or shaky, heart palpitations, difficulty falling asleep, and excessive sweating. 

The proper time for medication

Ensuring that you’re administering the medication at the proper times. 

This medication should be taken 30 to 60 minutes before breakfast or three or more hours before dinner for the best absorption into your bloodstream.

Taking it too soon before or after a meal or snack could reduce absorption to 64% from a high of 80% when fasting, according to the American Thyroid Association (ATA).

It takes some time

Even though levothyroxine is a hormone treatment, it’s not a magical pill that will automatically solve all the issues once you start taking it.

Initially, your body will take some time to get used to the medicine, and it could take a month or two to start feeling better. 

You should also see your doctor and test for blood levels of TSH, making adjustments to the dosage.

Don’t switch without asking your doctor

Be patient with your medication because switching from brand name to generic thyroid hormone or vice-versa could affect TSH levels, even if the dose is the same. 

Stick to the same drug type to keep your TSH levels steady unless your doctor asks you to make a change.

Think before adding T3

Synthetic triiodothyronine (T3) for hypothyroid symptoms persists despite normal TSH levels. Adding T3 to levothyroxine therapy might not make much of a difference. 

The body converts levothyroxine into T3 for some people with hypothyroidism, but for others, it might not. 

A combination treatment of levothyroxine and T3 is considered an experimental treatment for those whose fatigue, depression, weight gain, and other hypothyroidism symptoms haven’t waned even though taking levothyroxine alone has moved their TSH levels into the normal range. 

Skip natural thyroid medications

Don’t take additional supplements if your doctor hasn’t recommended them. Some are laced with thyroid hormones not listed on the label. 

Adding supplements would mean you’re getting too much. Any natural thyroid supplement may contain gland tissue from the thyroid, liver, heart, pancreas, and other animal organs. 

Side effects of levothyroxine

A woman is on the phone with her doctor, she's feeling quite irritable and having chest pain after taking her thyroid medicine Levothyroxine.

This medication could also lead to some unwanted effects. While not everyone might experience them but some people might, and these include:

  • Chest pain, discomfort, or tightness
  • Decreased urine output
  • Difficult or labored breathing
  • Difficulty with swallowing
  • Dilated neck veins
  • Extreme fatigue
  • Fainting
  • Fast, slow, irregular, pounding or racing heartbeat or pulse
  • Fever
  • Irregular breathing
  • Heat intolerance
  • Hives or welts, skin itching, rash, or redness
  • Irritability 
  • Menstrual changes
  • Nausea
  • Pain or discomfort in the arms, jaw, back, or neck
  • Sweating
  • Swelling of the eyes, face, lips, throat, or tongue
  • Tremors

Rare side effects include:

  • Blurred or double vision
  • Dizziness
  • Eye pain
  • Lack or slowing of normal growth in children
  • Limp or walk favoring one leg
  • Pain in the hip or knee
  • Seizures
  • Severe headaches

Why do I feel tired on levothyroxine?

Extreme tiredness is a commonly reported side effect of levothyroxine. Some people feel like this initially but gradually get used to the medication, and their body works fine. 

Feeling more tired on levothyroxine happens because hormones in your body have been effectively reduced.

Thyroxine is produced by the thyroid and is responsible for activating metabolic processes, energy production, and other functions in your body. 

Taking this medication would mean your cells aren’t able to receive signals from thyroxine as much as they once did. This means that the cells in your body cannot carry out their required functions effectively. 

This decrease in thyroxine means that cells work to total capacity, get tired, and experience fatigue. 

If you experience extreme tiredness or don’t feel well in general, even after a couple of months, it’s better to talk to your doctor to either increase or decrease your dosage. They might even switch medications. 


Why does levothyroxine make me feel sick?

Sometimes, taking a medication like levothyroxine which is supposed to treat your hormone issue, contains inactive ingredients which can cause hypersensitivity. 

These include urticaria, pruritus, skin rash, flushing, angioedema, various gastrointestinal symptoms, fever, arthralgia, serum sickness, and wheezing. 

How fast does levothyroxine lower TSH?

It might take several weeks for the medicine to take its full effect, and it could be somewhere in the first two months.

Most importantly, the effect depends on several factors, such as dosage, timing, other medical conditions, overall health, and more. 

What are the signs and symptoms of too much levothyroxine?

Symptoms of overdose include:

– Change in consciousness
– Cold, clammy skin
– Disorientation 
– Fast or weak pulse
– Lightheadedness
– Sudden headache
– Sudden loss of coordination
– Sudden slurring of speech

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Saumya Malik
I'm an ardent follower of everything good for the health and wellness of body and mind. I am passionate about providing effective solutions to general health and mental well-being issues and wants to help people achieve the same. When I'm not writing, you can find me curled up with a good book in a corner or cooking as a form of good mental therapy.

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