Levothyroxine SERB
Levothyroxine SERB is a thyroid hormone medicine used to treat severe underactive thyroid (myxedema coma) or when oral thyroid medication cannot be taken.
How to Use
Dosage
The dose varies based on your thyroid hormone levels, age, and how well you tolerate the medicine. For myxedema coma, the first dose is usually 200-500 micrograms. For underactive thyroid where oral treatment isn't possible, it usually starts at 25 micrograms daily and is slowly increased to 100-150 micrograms daily.
Method
This medicine is given as an injection into a muscle or vein. For myxedema coma, it is usually given slowly into a vein after being mixed with saline.
The first dose for severe conditions should not exceed 500 micrograms.
Possible Side Effects
- •Difficulty sleeping
- •Headache
- •Irregular heartbeat (palpitations)
- •Nervousness
- •Fast heartbeat
- •Increased pressure in the brain in children
- •Restlessness
- •Tremors (shaking)
- •Chest pain, heart rhythm problems (e.g., fast heartbeat)
- •Redness, circulatory collapse (sudden drop in blood pressure) in premature babies with very low birth weight
- •Loose stools (diarrhea), vomiting or nausea
- •Sweating
- •Muscle weakness, muscle cramps
- •Brittle bones (osteoporosis) with high doses of levothyroxine, especially in post-menopausal women, mainly with long-term treatment
- •Changes in menstrual cycle (menstrual disorders) in women
- •Poor heat tolerance
- •Fever
- •Weight loss
- •Allergic reactions (e.g., difficulty breathing, swelling of face/lips/tongue, rash, itching)
Important Warnings
- Do not use if you are allergic to levothyroxine sodium or any other ingredients in this medicine.
- Do not use if you have an active or unstable heart disease. This medicine can cause heart problems, especially in older patients, and you will be monitored closely.
- Do not use if you have adrenal insufficiency and are not receiving adequate treatment for it.
- Do not use if you have an overactive thyroid that is not adequately treated.
- Do not use if your pituitary gland is not working well.
Show 7 more warnings
- If you are pregnant, do not use levothyroxine with synthetic anti-thyroid medicines.
- Do not use this medicine for weight loss; it will not help if your thyroid hormone levels are normal, and taking too much or combining it with weight loss drugs can be dangerous.
- If you have diabetes, this medicine might increase your need for diabetes medication or insulin; your doctor will monitor you closely.
- If you have epilepsy, you will be monitored for an increased risk of seizures.
- If you are a post-menopausal woman at risk of osteoporosis (brittle bones), your doctor will keep the levothyroxine dose as low as possible and check your thyroid function often.
- If you have an allergic reaction, contact your doctor or healthcare professional immediately or go to the nearest emergency room.
- Tell your doctor or lab staff if you are taking or have recently taken biotin (Vitamin H/B7/B8), as it can affect thyroid hormone test results.
Use in Elderly Patients
Suitable for older adults. Calcium, iron, zinc, magnesium and aluminium reduce absorption. (updated 6.11.2023)