My sister has bipolar disorder. Can thyroid issues worsen it?

Question

Hello doctor,

My sister, aged 32, has bipolar disorder and is currently in a low mood phase. She is taking Lithium 600 mg and Quetiapine 100 mg at night.

Her recent lithium level was 0.8 mmol/L, which the doctor said is fine, but she still feels very tired and unfocused. So my concerns are -

Is this normal, even with correct medication levels?
Can vitamin or thyroid issues make symptoms worse?
Would therapy sessions actually help stabilize her mood, or only medicines work for that?
Also, how long do patients usually stay on mood stabilizers before trying to lower the dose safely without relapse of depression or mania?

Kindly help.

Answer 1

Hello,

Welcome to icliniq.com.

I read your query and can understand your concern.

Your sister is on Lithium, and it can definitely cause hypothyroidism.

Hypothyroidism can be a significant cause of depressive episodes and should be checked regularly. The same applies to anemia, iron, B12, and vitamin D levels. They not only contribute to depressive symptoms but also cause resistance in treatment.

Make sure Lithium levels were taken 12 hours post dose, as time duration difference can affect lithium levels. Lithium also affects the kidneys; therefore, eGFR (estimated glomerular filtration rate) should be measured.

Cognitive behavioral therapy works and is not an alternative but a compulsory component in bipolar disorder, and should be augmented to boost the effects of medicines. It works on dysfunctional thoughts and behaviors.

Other effective therapies include social rhythm therapy, family-focused therapy, and interpersonal therapy.

We usually connect mood stabilizers for at least two years if one episode or even more if multiple episodes. Tapering should be done very carefully as it can cause relapse of mania.

Lithium is a good mood stabilizer that prevents both manic and depressive episodes, but it is less effective in depressive episodes relapse prevention.

Therefore, her symptoms can be a sign of a new depressive episode. Quetiapine can also contribute to time sedation and lethargy.

Quetiapine can be reduced, and augmentation of Lamotrigine is the preferred option as her Lithium levels are within the normal range. But before adding, hypothyroidism, iron, vitamin B12, and vitamin D deficiency should be ruled out.

If hypothyroidism is present, augment it with Levothyroxine, which will improve her depressive symptoms and energy.

Other lifestyle modifications are also important, such as following strict sleep hygiene, taking a 30-minute evening walk, reducing caffeine and nicotine intake, and practicing relaxation exercises.

I hope this helps.

Thank you and take care.

Regards.