Tirosint 88mcg Capsules
Overview
What is this medicine?
How to Use This Medicine
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely.
Take your medication on an empty stomach, at least 30 to 60 minutes before breakfast.
Swallow the capsule whole - do not chew, break, or crush it.
Avoid taking iron products, antacids containing aluminum or magnesium, or calcium carbonate within 4 hours before or 4 hours after taking your medication.
If you take other medications, they may need to be taken at a different time than your current medication. Consult with your doctor or pharmacist to determine the best schedule.
Certain foods, such as soybean flour (found in infant formula), may interact with your medication. Discuss this with your doctor.
If you regularly consume grapefruit juice or eat grapefruit, talk to your doctor about potential interactions.
Be aware that different brands and forms of this medication are available. Do not switch between them without consulting your doctor.
Continuing Your Medication
Continue taking your medication as directed by your doctor or healthcare provider, even if you feel well.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry place, away from the bathroom.
Protect your medication from heat and light.
Do not remove your medication from the blister pack until you are ready to take it. Take the medication immediately after opening the blister pack, and do not store the removed medication for future use.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it is close to the time for your next dose, skip the missed dose and resume your regular schedule. Do not take two doses at the same time or take extra doses.
Lifestyle & Tips
- Take on an empty stomach, at least 30-60 minutes before breakfast, with a full glass of water.
- Wait at least 4 hours after taking levothyroxine before taking calcium, iron, antacids, or bile acid sequestrants.
- Avoid taking with coffee, soy products, or high-fiber foods as they can interfere with absorption.
- Take at the same time each day for consistent absorption.
- Do not switch between different brands or generic versions without consulting your doctor, as formulations can vary and affect absorption.
- Report any new or worsening symptoms to your doctor.
- Regular blood tests (TSH) are essential to ensure the correct dose.
Available Forms & Alternatives
Available Strengths:
- Tirosint 13mcg Capsules
- Tirosint 25mcg Capsules
- Tirosint 50mcg Capsules
- Tirosint 75mcg Capsules
- Tirosint 88mcg Capsules
- Tirosint 150mcg Capsules
- Tirosint 137mcg Capsules
- Tirosint 100mcg Capsules
- Tirosint 112mcg Capsules
- Tirosint 125mcg Capsules
- Tirosint 175mcg Capsules
- Tirosint 200mcg Capsules
- Tirosint-Sol 100mcg/ml Oral Sol
- Tirosint-Sol 137mcg/ml Oral Sol
- Tirosint-Sol 150mcg/ml Oral Sol
- Tirosint-Sol 175mcg/ml Oral Sol
- Tirosint-Sol 88mcg/ml Oral Sol
- Tirosint-Sol 200mcg/ml Oral Sol
- Tirosint-Sol 13mcg/ml Oral Sol
- Tirosint-Sol 25mcg/ml Oral Sol
- Tirosint-Sol 50mcg/ml Oral Sol
- Tirosint-Sol 112mcg/ml Oral Sol
- Tirosint-Sol 75mcg/ml Oral Sol
- Tirosint-Sol 125mcg/ml Oral Sol
- Tirosint-Sol 37.5mcg/ml Oral Sol
- Tirosint-Sol 44mcg/ml Oral Sol
- Tirosint-Sol 62.5mcg/ml Oral Sol
- Tirosint 37.5mcg Capsules
- Tirosint 44mcg Capsules
- Tirosint 62.5mcg Capsules
Generic Alternatives:
Dosing & Administration
Adult Dosing
Condition-Specific Dosing:
Pediatric Dosing
Dose Adjustments
Renal Impairment:
Hepatic Impairment:
Pharmacology
Mechanism of Action
Pharmacokinetics
Absorption:
Distribution:
Elimination:
Pharmacodynamics
Safety & Warnings
BLACK BOX WARNING
Side Effects
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of high blood pressure, including:
+ Severe headache or dizziness
+ Passing out
+ Changes in eyesight
Chest pain or pressure
Fast or abnormal heartbeat
Shortness of breath
Sudden weight gain or swelling in the arms or legs
Headache
Feeling tired or weak
Changes in appetite
Unintentional weight changes
Diarrhea, stomach cramps, or vomiting
Mood changes, such as feeling irritable, nervous, excitable, anxious, or restless
Shakiness
Trouble sleeping
Sensitivity to heat
Excessive sweating
Fever
Muscle cramps
Muscle weakness
Flushing
Bone pain
Changes in menstrual periods
Additional Side Effects in Children:
Hip or knee pain
Limping
Additional Side Effects in Infants:
Changes in the shape of the head and face
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor:
Hair loss (usually temporary and resolves on its own within the first few months of treatment)
Reporting Side Effects
This is not an exhaustive list of possible side effects. If you have questions or concerns, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Symptoms of overmedication (hyperthyroidism): Chest pain, rapid or irregular heartbeat, shortness of breath, excessive sweating, heat intolerance, nervousness, tremor, insomnia, diarrhea, significant weight loss.
- Symptoms of undermedication (hypothyroidism): Persistent fatigue, weight gain, constipation, cold intolerance, dry skin, hair loss, depression, memory problems.
Before Using This Medicine
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
Certain health conditions, including:
+ An overactive thyroid gland
+ A weak adrenal gland
+ Difficulty swallowing
This list is not exhaustive, and it is crucial to discuss all your health problems with your doctor.
Additionally, provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter (OTC) medications you are taking
Any natural products or vitamins you are using
Any health problems you have
It is vital to verify that it is safe to take this medication with all your other medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor.
Precautions & Cautions
It is crucial that you inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. To ensure uninterrupted treatment, do not allow your supply of this medication to run out. Please note that it may take several weeks to experience the full effects of this drug.
Special Considerations
If you have diabetes (high blood sugar), consult with your doctor, as this medication may affect your blood sugar control. Your doctor may need to adjust your diabetes medications. Be sure to monitor your blood sugar levels as directed by your doctor and undergo regular blood tests as recommended.
If you are taking biotin or a product containing biotin, stop taking it at least 2 days before having your thyroid levels checked to ensure accurate test results.
Potential Risks and Side Effects
High doses of this medication may increase the risk of osteoporosis (weak bones), particularly after menopause. Discuss your individual risk factors with your doctor, who can help determine if you are at higher risk.
This medication may also affect fertility, potentially leading to difficulties in getting pregnant or fathering a child. If you plan to conceive, consult with your doctor before starting treatment.
Age-Related Considerations
If you are 65 or older, use this medication with caution, as you may be more susceptible to side effects.
Pregnancy and Breastfeeding
Inform your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. Your doctor will discuss the benefits and risks of this medication to both you and your baby.
Pediatric Patients
If you are giving this medication to a child, consult with your doctor if the child's weight changes, as the dosage may need to be adjusted. Never give your child more of this medication than prescribed, as this may increase the risk of severe side effects.
In some cases, this medication may affect growth in children and teenagers. Regular growth checks may be necessary. Consult with your doctor to discuss any concerns.
Overdose Information
Overdose Symptoms:
- Palpitations
- Tachycardia
- Arrhythmias
- Chest pain
- Tremor
- Nervousness
- Insomnia
- Diarrhea
- Weight loss
- Increased appetite
- Fever
- Heat intolerance
- Seizures (rare)
- Heart failure (rare, especially in elderly or those with underlying cardiac disease)
What to Do:
Seek immediate medical attention or call Poison Control at 1-800-222-1222. Treatment is symptomatic and supportive, often involving beta-blockers for cardiac symptoms and measures to reduce absorption if recent ingestion.
Drug Interactions
Major Interactions
- Amiodarone (can cause hypo- or hyperthyroidism)
- Oral anticoagulants (may increase anticoagulant effect)
- Insulin/Oral Hypoglycemics (may increase insulin/hypoglycemic requirements)
- Digoxin (may decrease digoxin levels)
- Cholestyramine, Colestipol, Sevelamer, Sucralfate, Kayexalate (decrease levothyroxine absorption)
- Iron supplements, Calcium supplements, Aluminum-containing antacids (decrease levothyroxine absorption)
- Proton Pump Inhibitors (PPIs) and H2-blockers (reduce gastric acidity, impair absorption)
- Orlistat (may decrease levothyroxine absorption)
- Tyrosine Kinase Inhibitors (e.g., Sunitinib, Imatinib, Pazopanib) (can alter thyroid function, increase levothyroxine requirements)
- Estrogens (increase TBG, may increase levothyroxine requirements)
- Androgens/Anabolic Steroids (decrease TBG, may decrease levothyroxine requirements)
- SSRIs (may affect thyroid function tests, usually not clinically significant)
- Phenytoin, Carbamazepine, Rifampin, Phenobarbital (increase levothyroxine metabolism)
- Beta-blockers (may decrease peripheral conversion of T4 to T3)
- Glucocorticoids (may decrease peripheral conversion of T4 to T3)
Moderate Interactions
- Soy products (decrease absorption)
- Dietary fiber (decrease absorption)
- Coffee (decrease absorption)
- Grapefruit juice (may affect absorption)
- Certain foods (e.g., walnuts, cottonseed meal) (decrease absorption)
Monitoring
Baseline Monitoring
Rationale: Primary indicator of thyroid function and adequacy of levothyroxine replacement.
Timing: Before initiating therapy.
Rationale: Measures unbound, active T4. Useful in certain conditions (e.g., central hypothyroidism, pregnancy).
Timing: Before initiating therapy.
Rationale: To establish baseline and track improvement.
Timing: Before initiating therapy.
Routine Monitoring
Frequency: Every 4-6 weeks after initiation or dose change, then every 6-12 months once stable.
Target: 0.4-4.0 mIU/L (for primary hypothyroidism, individualized for other conditions).
Action Threshold: Adjust dose if TSH is outside target range.
Frequency: Consider if TSH is suppressed or elevated, or in central hypothyroidism, or during pregnancy.
Target: 0.8-1.8 ng/dL (or laboratory specific reference range).
Action Threshold: Adjust dose if Free T4 is outside target range, especially if TSH is not reliable.
Frequency: At each visit.
Target: Resolution of hypothyroid symptoms (e.g., fatigue, weight gain, constipation, cold intolerance).
Action Threshold: Consider dose adjustment if symptoms persist despite target TSH.
Symptom Monitoring
- Fatigue
- Weight changes (gain or loss)
- Constipation
- Cold intolerance
- Dry skin
- Hair loss
- Bradycardia
- Depression
- Memory impairment
- Muscle aches
- Menstrual irregularities
- Nervousness
- Palpitations
- Tremor
- Heat intolerance
- Diarrhea
- Insomnia
Special Patient Groups
Pregnancy
Levothyroxine is Category A and is essential for fetal neurological development. Hypothyroidism during pregnancy can lead to adverse maternal and fetal outcomes. Dose requirements often increase during pregnancy.
Trimester-Specific Risks:
Lactation
Levothyroxine is compatible with breastfeeding (L1 - Safest). Minimal amounts are excreted into breast milk and do not adversely affect the infant.
Pediatric Use
Dosing is weight-based and higher per kg than in adults, especially in infants and young children, due to higher metabolic rates and rapid growth. Regular monitoring of TSH and Free T4 is crucial to ensure proper growth and neurocognitive development. Congenital hypothyroidism requires prompt treatment to prevent irreversible intellectual disability.
Geriatric Use
Lower initial doses (e.g., 12.5-25 mcg/day) are recommended, especially in patients with underlying cardiac disease, due to increased sensitivity to thyroid hormones and potential for cardiac adverse effects. Dose adjustments should be made in smaller increments and less frequently. Monitor for signs of cardiac toxicity.
Clinical Information
Clinical Pearls
- Tirosint capsules contain only levothyroxine, glycerin, and water, making them suitable for patients with sensitivities to common excipients found in tablet formulations (e.g., lactose, gluten, dyes).
- Tirosint is available in a wide range of strengths, allowing for precise dose titration.
- Consistency is key: Patients should take levothyroxine at the same time each day, on an empty stomach, and consistently with or without other medications/foods that affect absorption.
- Patients should be advised not to switch between different levothyroxine products (brand to generic, or different generics) without consulting their physician, as bioavailability differences can necessitate dose adjustments.
- TSH is the primary monitoring parameter for primary hypothyroidism. Free T4 is useful in central hypothyroidism, pregnancy, or when TSH is unreliable.
- Symptoms of hyperthyroidism (overmedication) or persistent hypothyroidism (undermedication) should prompt TSH re-evaluation.
- Educate patients about the black box warning regarding use for weight loss.
- Many medications and supplements can interfere with levothyroxine absorption or metabolism; a thorough medication history is crucial.
Alternative Therapies
- Liothyronine (T3, Cytomel): Used less commonly, often for specific indications or in combination with levothyroxine.
- Desiccated Thyroid Extract (Armour Thyroid, NP Thyroid): Natural thyroid hormone derived from porcine thyroid glands, containing both T4 and T3. Dosing can be less precise due to variable hormone content.
- Levothyroxine/Liothyronine combination products (e.g., Thyrolar): Synthetic combination of T4 and T3.