Thyroid Np 1gr (60mg) Tablets
WARNING: Do not use this drug for weight loss. Severe and sometimes deadly side effects may happen with this drug if it is taken in large doses or with other drugs for weight loss. If you have questions, talk with the doctor. @ COMMON USES: It is used to add thyroid hormone to the body.It is used to treat or prevent an enlarged thyroid.It is used to manage thyroid cancer.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Thyroid hormone replacement
Pharmacologic Class
Thyroid hormones
Pregnancy Category
Category A
FDA Approved
Jan 1970
DEA Schedule
Not Controlled
Overview
What is this medicine?
This medication is a natural thyroid hormone replacement, made from animal thyroid glands. It contains both T4 and T3 hormones, which are essential for your body's metabolism, energy, and overall function. It's used to treat an underactive thyroid (hypothyroidism) when your body doesn't produce enough of these hormones on its own.
How to Use This Medicine
Taking Your Medication Correctly
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. It's best to take this medication on an empty stomach.
Important Notes About Different Brands and Forms
There are various brands and forms of this medication available. Do not switch between different brands or forms without first consulting your doctor.
Interactions with Other Medications and Foods
Do not take colesevelam, colestipol, or cholestyramine within 4 hours before or 4 hours after taking this medication. Additionally, some foods like soybean flour (found in infant formula) may affect how this medication works in your body. Discuss this with your doctor.
Establishing a Routine
Take your medication at the same time every day. Continue taking your medication as directed by your doctor or healthcare provider, even if you're feeling well.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry place, avoiding the bathroom. Keep all medications in a safe location, out of reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you're unsure about the best way to dispose of your medication, consult your pharmacist. You may also have access to drug take-back programs in your area.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember. However, if it's 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.
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. It's best to take this medication on an empty stomach.
Important Notes About Different Brands and Forms
There are various brands and forms of this medication available. Do not switch between different brands or forms without first consulting your doctor.
Interactions with Other Medications and Foods
Do not take colesevelam, colestipol, or cholestyramine within 4 hours before or 4 hours after taking this medication. Additionally, some foods like soybean flour (found in infant formula) may affect how this medication works in your body. Discuss this with your doctor.
Establishing a Routine
Take your medication at the same time every day. Continue taking your medication as directed by your doctor or healthcare provider, even if you're feeling well.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry place, avoiding the bathroom. Keep all medications in a safe location, out of reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you're unsure about the best way to dispose of your medication, consult your pharmacist. You may also have access to drug take-back programs in your area.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember. However, if it's 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 this medication consistently at the same time each day, preferably in the morning on an empty stomach, at least 30-60 minutes before food or other medications.
- Avoid taking calcium, iron, antacids, or fiber supplements within 4 hours of your thyroid medication, as they can interfere with absorption.
- Inform your doctor about all other medications, supplements, and herbal products you are taking, as many can interact with thyroid hormones.
- Do not stop taking this medication without consulting your doctor, even if you feel better. Lifelong therapy is often required.
- Do not use this medication for weight loss; it is ineffective and potentially dangerous for that purpose.
Available Forms & Alternatives
Dosing & Administration
Adult Dosing
Standard Dose:
Highly individualized; typical maintenance dose for hypothyroidism is 60-120 mg (1-2 grains) daily, adjusted based on TSH and clinical response.
Dose Range:
15 - 300 mg
Condition-Specific Dosing:
hypothyroidism_initial:
Initial dose typically 15-30 mg (1/4-1/2 grain) daily, increased by 15-30 mg increments every 2-3 weeks until euthyroid state is achieved.
myxedema_coma:
Not typically used; IV levothyroxine is preferred.
Pediatric Dosing
Neonatal:
Initial 7.5-15 mg (1/8-1/4 grain) daily, adjusted based on TSH and T4. Crucial for neurological development.
Infant:
Initial 15-30 mg (1/4-1/2 grain) daily, adjusted based on TSH and T4.
Child:
Initial 30-60 mg (1/2-1 grain) daily, adjusted based on TSH and T4.
Adolescent:
Initial 30-60 mg (1/2-1 grain) daily, adjusted based on TSH and T4, often approaching adult doses.
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment needed, monitor thyroid function.
Moderate:
No specific adjustment needed, monitor thyroid function.
Severe:
No specific adjustment needed, monitor thyroid function.
Dialysis:
No specific adjustment needed, monitor thyroid function. Thyroid hormones are highly protein-bound and not significantly removed by dialysis.
Hepatic Impairment:
Mild:
No specific adjustment needed, monitor thyroid function.
Moderate:
No specific adjustment needed, monitor thyroid function.
Severe:
No specific adjustment needed, monitor thyroid function. Metabolism may be altered, but dose adjustment is typically based on thyroid function tests.
Pharmacology
Mechanism of Action
Thyroid, Desiccated is a natural product derived from porcine thyroid glands, containing both levothyroxine (T4) and liothyronine (T3). These hormones exert their physiological effects by binding to specific nuclear thyroid hormone receptors, regulating gene expression and controlling numerous metabolic processes, including protein, fat, and carbohydrate metabolism, and influencing growth and development.
Pharmacokinetics
Absorption:
Bioavailability:
Variable (approximately 48-80% for T4, higher for T3), influenced by gut integrity and co-administered substances.
Tmax:
T4: 2-4 hours; T3: 1-2 hours
FoodEffect:
Decreased absorption when taken with food, especially fiber, calcium, iron, and soy products. Should be taken on an empty stomach.
Distribution:
Vd:
T4: 10-12 L; T3: 0.46 L/kg
ProteinBinding:
T4: >99% (primarily to thyroxine-binding globulin [TBG], transthyretin, and albumin); T3: ~99% (less avidly than T4)
CnssPenetration:
Limited for T4; better for T3
Elimination:
HalfLife:
T4: 6-7 days; T3: ~1 day
Clearance:
T4: 1.1 L/day; T3: 2.3 L/day
ExcretionRoute:
Primarily renal (conjugated metabolites), some biliary/fecal excretion.
Unchanged:
Minimal
Pharmacodynamics
OnsetOfAction:
Gradual, clinical effects typically seen within 3-5 days for T3 component, and 3-4 weeks for full T4 effect.
PeakEffect:
Weeks to achieve steady-state and full therapeutic effect.
DurationOfAction:
Long, due to the long half-life of T4 (up to several weeks after discontinuation).
Safety & Warnings
BLACK BOX WARNING
Thyroid hormones, including Thyroid, Desiccated, should not be used for the treatment of obesity or for weight reduction. In euthyroid patients, doses within the range of daily hormonal requirements are ineffective for weight reduction. Larger doses may produce serious or even life-threatening manifestations of toxicity, particularly when given in association with sympathomimetic amines such as those used for their anorectic effects.
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
While rare, some people may experience severe and potentially life-threatening side effects when 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
Shakiness
Trouble sleeping
Sensitivity to heat
Excessive sweating
Changes in appetite
Unintentional weight changes
Diarrhea
Stomach cramps
Vomiting
Irritability, nervousness, excitability, anxiety, or other mood changes
Fever
Muscle cramps
Muscle weakness
Flushing
Bone pain
Changes in menstrual periods
Other Possible Side Effects
Like all medications, this drug can cause side effects. However, many people may not experience any side effects or may only have mild ones. If you are bothered by any of the following side effects or if they 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 all possible side effects. If you have questions or concerns about side effects, 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.
While rare, some people may experience severe and potentially life-threatening side effects when 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
Shakiness
Trouble sleeping
Sensitivity to heat
Excessive sweating
Changes in appetite
Unintentional weight changes
Diarrhea
Stomach cramps
Vomiting
Irritability, nervousness, excitability, anxiety, or other mood changes
Fever
Muscle cramps
Muscle weakness
Flushing
Bone pain
Changes in menstrual periods
Other Possible Side Effects
Like all medications, this drug can cause side effects. However, many people may not experience any side effects or may only have mild ones. If you are bothered by any of the following side effects or if they 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 all possible side effects. If you have questions or concerns about side effects, 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 too much thyroid hormone (hyperthyroidism): rapid heart rate, palpitations, chest pain, nervousness, irritability, insomnia, tremor, excessive sweating, heat intolerance, diarrhea, unexplained weight loss.
- Symptoms of too little thyroid hormone (hypothyroidism): extreme fatigue, weight gain, cold intolerance, constipation, dry skin, hair loss, depression, slow heart rate, muscle aches.
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
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 symptoms you experienced as a result of the allergy.
Certain health conditions, including:
+ Overactive thyroid gland (hyperthyroidism)
+ Weak adrenal gland (adrenal insufficiency)
This list is not exhaustive, and it is crucial to discuss all your health problems and medications with your doctor.
To ensure your safety, provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter (OTC) medications you are taking
Natural products and vitamins you are using
* Any health problems you have
Before starting, stopping, or changing the dose of any medication, including this one, consult with your doctor to confirm it is safe for you to do so.
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 symptoms you experienced as a result of the allergy.
Certain health conditions, including:
+ Overactive thyroid gland (hyperthyroidism)
+ Weak adrenal gland (adrenal insufficiency)
This list is not exhaustive, and it is crucial to discuss all your health problems and medications with your doctor.
To ensure your safety, provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter (OTC) medications you are taking
Natural products and vitamins you are using
* Any health problems you have
Before starting, stopping, or changing the dose of any medication, including this one, consult with your doctor to confirm it is safe for you to do so.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. To ensure continuous treatment, do not allow your supply of this drug to run out. Please note that it may take several weeks for the full effects of this medication to become apparent.
If you have diabetes (high blood sugar), consult with your doctor, as this drug may occasionally affect blood sugar control. As a result, your diabetes medications may need to be adjusted. Adhere to your doctor's instructions for monitoring your blood sugar levels and undergo blood work and other laboratory tests as directed.
If you are taking biotin or any products containing biotin, discontinue use at least 2 days prior to having your thyroid levels checked. This medication is derived from pork (pig) thyroid tissue, which carries a minimal risk of transmitting a viral disease. Although no cases have been reported, if you have concerns, discuss them with your doctor.
If you are 65 years or older, exercise caution when using this drug, as you may be more susceptible to side effects. If you are pregnant, planning to become pregnant, or breastfeeding, consult with your doctor to weigh the benefits and risks of this medication to both you and your baby.
If you have diabetes (high blood sugar), consult with your doctor, as this drug may occasionally affect blood sugar control. As a result, your diabetes medications may need to be adjusted. Adhere to your doctor's instructions for monitoring your blood sugar levels and undergo blood work and other laboratory tests as directed.
If you are taking biotin or any products containing biotin, discontinue use at least 2 days prior to having your thyroid levels checked. This medication is derived from pork (pig) thyroid tissue, which carries a minimal risk of transmitting a viral disease. Although no cases have been reported, if you have concerns, discuss them with your doctor.
If you are 65 years or older, exercise caution when using this drug, as you may be more susceptible to side effects. If you are pregnant, planning to become pregnant, or breastfeeding, consult with your doctor to weigh the benefits and risks of this medication to both you and your baby.
Overdose Information
Overdose Symptoms:
- Signs and symptoms of hyperthyroidism (thyrotoxicosis): headache, irritability, nervousness, sweating, tachycardia, palpitations, chest pain, arrhythmias, tremor, insomnia, heat intolerance, fever, weight loss, diarrhea, menstrual irregularities, convulsions, shock, heart failure, coma.
What to Do:
Seek immediate medical attention or call a poison control center (1-800-222-1222). Management is supportive and symptomatic, often involving beta-blockers for cardiac symptoms and measures to reduce absorption if recent ingestion.
Drug Interactions
Contraindicated Interactions
- Not for use in patients with uncorrected adrenal insufficiency or acute thyrotoxicosis.
Major Interactions
- Anticoagulants (e.g., warfarin): May increase anticoagulant effect by increasing catabolism of vitamin K-dependent clotting factors. Monitor INR.
- Sympathomimetics (e.g., epinephrine, norepinephrine): Increased risk of cardiac adverse effects.
- Insulin/Oral Hypoglycemics: May increase requirements for antidiabetic agents due to increased glucose metabolism. Monitor blood glucose.
- Digoxin: May decrease digoxin levels or effect. Monitor digoxin levels.
- Cholestyramine, Colestipol, Sevelamer, Sucralfate, Calcium Carbonate, Iron Salts, Aluminum Hydroxide, Proton Pump Inhibitors (PPIs), H2 Blockers: Decrease absorption of thyroid hormones. Separate administration by at least 4 hours (PPIs/H2 blockers by longer if possible).
Moderate Interactions
- Phenytoin, Carbamazepine, Rifampin, Phenobarbital: May increase metabolism of thyroid hormones, requiring higher doses.
- Amiodarone: Can cause hypo- or hyperthyroidism and alter thyroid hormone metabolism.
- Beta-blockers: May decrease conversion of T4 to T3.
- Oral Contraceptives/Estrogens: May increase TBG levels, requiring higher thyroid hormone doses.
- SSRIs (e.g., sertraline): May increase thyroid hormone requirements.
- Iodine-containing products: Can affect thyroid function.
Minor Interactions
- Dietary fiber: May decrease absorption.
- Soy products: May decrease absorption.
Monitoring
Baseline Monitoring
Thyroid Stimulating Hormone (TSH)
Rationale: Primary indicator of thyroid function and adequacy of replacement therapy.
Timing: Prior to initiation of therapy.
Free Thyroxine (Free T4)
Rationale: Assesses circulating unbound T4 levels.
Timing: Prior to initiation of therapy.
Free Triiodothyronine (Free T3)
Rationale: Assesses circulating unbound T3 levels, which can be more variable with desiccated thyroid.
Timing: Prior to initiation of therapy.
Clinical Symptoms of Hypothyroidism
Rationale: To establish baseline and track improvement.
Timing: Prior to initiation of therapy.
Routine Monitoring
Thyroid Stimulating Hormone (TSH)
Frequency: Every 4-6 weeks after initiation or dose change, then annually once stable.
Target: Typically 0.4-4.0 mIU/L (individualized based on patient factors and clinical response).
Action Threshold: Above or below target range indicates need for dose adjustment.
Free Thyroxine (Free T4)
Frequency: Every 4-6 weeks after initiation or dose change, then annually once stable.
Target: Typically within the upper half of the reference range (e.g., 1.0-1.7 ng/dL).
Action Threshold: Below or above target range, especially if TSH is also abnormal.
Free Triiodothyronine (Free T3)
Frequency: May be monitored periodically, especially if symptoms persist despite normal TSH/T4.
Target: Typically within the reference range, but can be higher than with levothyroxine monotherapy.
Action Threshold: Significantly elevated levels may indicate overtreatment, even with normal TSH.
Clinical Symptoms (e.g., fatigue, weight, mood, heart rate)
Frequency: At every visit.
Target: Resolution of hypothyroid symptoms, absence of hyperthyroid symptoms.
Action Threshold: Persistence of hypothyroid symptoms or emergence of hyperthyroid symptoms.
Symptom Monitoring
- Fatigue
- Weight changes (gain or loss)
- Cold intolerance
- Constipation
- Dry skin/hair loss
- Depression/mood changes
- Bradycardia (slow heart rate)
- Muscle aches/weakness
- Memory impairment
- Nervousness/anxiety
- Palpitations/tachycardia (fast heart rate)
- Heat intolerance
- Diarrhea
- Tremor
- Insomnia
- Excessive sweating
Special Patient Groups
Pregnancy
Thyroid hormone replacement is essential during pregnancy for both maternal and fetal health. Untreated maternal hypothyroidism can lead to adverse pregnancy outcomes (e.g., miscarriage, preeclampsia, preterm birth) and impaired fetal neurodevelopment. Dose requirements often increase during pregnancy.
Trimester-Specific Risks:
First Trimester:
Crucial for fetal brain development. Inadequate maternal thyroid hormone can lead to irreversible neurological damage in the fetus.
Second Trimester:
Continued need for adequate thyroid hormone to support fetal growth and development.
Third Trimester:
Dose may need to be further adjusted as pregnancy progresses.
Lactation
Thyroid hormones are excreted in breast milk in small amounts, but are generally considered compatible with breastfeeding. Adequate maternal thyroid hormone levels are important for the mother's well-being and milk production.
Infant Risk:
L1 (Safest) - No known adverse effects on breastfed infants at therapeutic maternal doses. Monitoring infant thyroid function is not routinely necessary unless there are concerns.
Pediatric Use
Thyroid hormone replacement is critical for normal growth, development, and intellectual function in children with hypothyroidism. Dosing is weight-based and adjusted frequently based on TSH and T4 levels. Untreated congenital hypothyroidism can lead to severe and irreversible intellectual disability.
Geriatric Use
Elderly patients may be more sensitive to the effects of thyroid hormones, particularly cardiac effects. Initial doses should be lower, and dose increases should be more gradual. Careful monitoring for signs of cardiac dysfunction (e.g., angina, arrhythmias) is essential.
Clinical Information
Clinical Pearls
- Desiccated thyroid contains both T4 and T3, which may appeal to patients who feel suboptimal on levothyroxine (T4) monotherapy, though evidence for superior outcomes is mixed.
- Dosing is highly individualized and requires careful monitoring of TSH, Free T4, and Free T3, along with clinical symptoms. TSH may be suppressed even when the patient is euthyroid due to the T3 component.
- Consistency in administration (same time, empty stomach, away from interacting substances) is crucial for stable absorption and therapeutic effect.
- Patients should be educated that this medication is not for weight loss and misuse can lead to serious cardiac and metabolic complications.
- Due to its animal origin, some patients may have concerns regarding purity, consistency, or ethical considerations, though modern manufacturing aims for standardization.
Alternative Therapies
- Levothyroxine (synthetic T4, e.g., Synthroid, Levoxyl, Tirosint) - most commonly prescribed.
- Liothyronine (synthetic T3, e.g., Cytomel, Triostat) - typically used in combination with levothyroxine or for specific conditions.
- Compounded T4/T3 combinations (custom ratios).
Cost & Coverage
Average Cost:
Varies widely, typically $15-$50 per 30 tablets (60mg)
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 (preferred generic/brand)
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about your medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it happened.