Tacrolimus 5mg (five Mg) Capsules
WARNING: This drug may raise the chance of getting cancer like lymphoma or skin cancer. Talk with the doctor.Have your skin checked. Tell your doctor if you have any skin changes like a new wart, skin sore or reddish bump that bleeds or does not heal, or a change in the color or size of a mole.Call your doctor right away if you have a swollen gland, night sweats, shortness of breath, or weight loss without trying.This drug may raise the chance of very bad and sometimes deadly infections. Talk with the doctor.Call your doctor right away if you have any signs of infection like fever, chills, flu-like signs, very bad sore throat, ear or sinus pain, cough, more sputum or change in color of sputum, pain with passing urine, mouth sores, or a wound that will not heal. @ COMMON USES: It is used to keep the body from harming the organ after an organ transplant.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Immunosuppressant
Pharmacologic Class
Calcineurin inhibitor
Pregnancy Category
Category C
FDA Approved
Apr 1994
DEA Schedule
Not Controlled
Overview
What is this medicine?
Tacrolimus is a medicine used to prevent your body from rejecting a transplanted organ (like a kidney, liver, or heart). It works by weakening your immune system so it doesn't attack the new organ. Because it weakens your immune system, it's very important to take it exactly as prescribed and to be careful about infections.
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. Continue taking your medication as directed by your doctor or healthcare provider, even if you start to feel better.
Take your medication at the same time every day. You can take it with or without food, but be consistent in how you take it each time. If you take it with food, always take it with food. If you take it on an empty stomach, always take it on an empty stomach.
Swallow your medication whole, without chewing, opening, or crushing it.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry place, away from the bathroom. Keep all medications in a safe location, out of the 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 by your pharmacist. Check with your pharmacist for guidance on the best way to dispose of your medication. You may also want to explore 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 make up for a missed dose.
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. Continue taking your medication as directed by your doctor or healthcare provider, even if you start to feel better.
Take your medication at the same time every day. You can take it with or without food, but be consistent in how you take it each time. If you take it with food, always take it with food. If you take it on an empty stomach, always take it on an empty stomach.
Swallow your medication whole, without chewing, opening, or crushing it.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry place, away from the bathroom. Keep all medications in a safe location, out of the 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 by your pharmacist. Check with your pharmacist for guidance on the best way to dispose of your medication. You may also want to explore 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 make up for a missed dose.
Lifestyle & Tips
- Take tacrolimus at the same time each day, consistently with or without food (preferably on an empty stomach) to maintain stable levels.
- Do not switch between different brands or formulations of tacrolimus without your doctor's explicit instruction, as doses are not interchangeable.
- Avoid grapefruit and grapefruit juice, as they can significantly increase tacrolimus levels and cause side effects.
- Avoid St. John's Wort, as it can significantly decrease tacrolimus levels and lead to organ rejection.
- Avoid live vaccines while taking tacrolimus.
- Practice good hygiene (frequent hand washing) and avoid contact with sick individuals to reduce the risk of infection.
- Use sun protection (sunscreen, protective clothing) as tacrolimus can increase the risk of skin cancer.
- Report any new or worsening symptoms to your healthcare provider immediately.
Available Forms & Alternatives
Available Strengths:
- Tacrolimus 1mg Capsules
- Tacrolimus 0.5mg (half Mg) Capsules
- Tacrolimus 5mg (five Mg) Capsules
- Tacrolimus 1mg Caps (bx)
- Tacrolimus 0.5mg (half Mg) Cap(bx)
- Tacrolimus 5mg (five Mg)caps (bx)
- Tacrolimus 0.03% Ointment 30gm
- Tacrolimus 0.03% Ointment 60gm
- Tacrolimus 0.03% Ointment 100gm
- Tacrolimus 0.1% Ointment 30gm
- Tacrolimus 0.1% Ointment 60gm
- Tacrolimus 0.1% Ointment 100gm
Dosing & Administration
Adult Dosing
Standard Dose:
Highly individualized based on therapeutic drug monitoring (TDM). Initial doses vary by organ transplant type and formulation (immediate-release vs. extended-release).
Dose Range:
0.05 - 0.3 mg
Condition-Specific Dosing:
Liver Transplant (immediate-release):
0.1-0.15 mg/kg/day orally in two divided doses, initiated 6-12 hours post-transplant.
Kidney Transplant (immediate-release):
0.2 mg/kg/day orally in two divided doses, initiated within 24 hours of transplant.
Heart Transplant (immediate-release):
0.075 mg/kg/day orally in two divided doses, initiated within 6 hours of transplant.
Pediatric Dosing
Neonatal:
Not established, use with extreme caution and TDM.
Infant:
Dosing is highly individualized based on TDM. Generally, higher doses per kg are required compared to adults due to faster clearance. Initial doses for liver transplant: 0.15-0.2 mg/kg/day orally in two divided doses.
Child:
Dosing is highly individualized based on TDM. Generally, higher doses per kg are required compared to adults due to faster clearance. Initial doses for liver transplant: 0.15-0.2 mg/kg/day orally in two divided doses.
Adolescent:
Dosing is highly individualized based on TDM. May require higher doses per kg than adults, but generally less than younger children.
Dose Adjustments
Renal Impairment:
Mild:
No specific dose adjustment required, but monitor renal function closely.
Moderate:
No specific dose adjustment required, but monitor renal function closely. Consider lower end of dosing range.
Severe:
No specific dose adjustment required, but monitor renal function closely. Consider lower end of dosing range and more frequent TDM.
Dialysis:
Tacrolimus is highly protein-bound and not significantly removed by dialysis. No supplemental dose needed post-dialysis, but monitor trough levels closely.
Hepatic Impairment:
Mild:
Consider lower initial doses (e.g., 25-50% of standard dose) and titrate based on TDM.
Moderate:
Consider lower initial doses (e.g., 25-50% of standard dose) and titrate based on TDM.
Severe:
Consider lower initial doses (e.g., 25-50% of standard dose) and titrate based on TDM. Patients with severe hepatic impairment may have significantly reduced clearance.
Pharmacology
Mechanism of Action
Tacrolimus is a calcineurin inhibitor. It binds to the immunophilin FKBP-12 (FK506-binding protein), forming a complex that inhibits calcineurin, a phosphatase. This inhibition prevents the dephosphorylation of nuclear factor of activated T-cells (NF-AT), thereby inhibiting its translocation into the nucleus. This ultimately blocks the transcription of early T-cell activation genes, such as interleukin-2 (IL-2), IL-3, IL-4, IL-5, GM-CSF, and TNF-alpha, leading to the inhibition of T-lymphocyte activation and proliferation.
Pharmacokinetics
Absorption:
Bioavailability:
20-25% (highly variable, 4-89%)
Tmax:
1-3 hours
FoodEffect:
Food, especially high-fat meals, significantly decreases the rate and extent of absorption (AUC and Cmax can decrease by 27% and 50% respectively). Should be taken consistently, either with or without food, but preferably on an empty stomach.
Distribution:
Vd:
0.85-1.94 L/kg
ProteinBinding:
98.8% (primarily to albumin and alpha-1-acid glycoprotein, also extensively binds to erythrocytes)
CnssPenetration:
Limited (low concentrations in CSF, but neurotoxicity can occur)
Elimination:
HalfLife:
Approximately 12-18 hours (range 4-40 hours, highly variable)
Clearance:
0.04-0.08 L/hr/kg
ExcretionRoute:
Primarily fecal (92-95%), with a small amount excreted renally (2-3%)
Unchanged:
<1% (renal excretion)
Pharmacodynamics
OnsetOfAction:
Immunosuppressive effects begin within hours, but clinical efficacy for rejection prevention is observed over days to weeks.
PeakEffect:
Achieved once steady-state trough concentrations are reached (typically 2-3 days with consistent dosing).
DurationOfAction:
Dependent on maintaining therapeutic trough concentrations.
Safety & Warnings
BLACK BOX WARNING
Increased risk of developing serious infections and malignancies (e.g., lymphoma, skin cancer) due to immunosuppression. Increased risk of nephrotoxicity and neurotoxicity. Administer under the supervision of a physician experienced in immunosuppressive therapy and management of organ transplant patients. Tacrolimus extended-release capsules (Astagraf XL) and tacrolimus extended-release tablets (Envarsus XR) are not interchangeable with tacrolimus immediate-release capsules (Prograf) on a milligram-to-milligram basis. Switching between formulations must be done under physician supervision with therapeutic drug monitoring.
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
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 medical attention immediately:
Allergic Reaction: 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; or swelling of the mouth, face, lips, tongue, or throat.
Kidney Problems: Inability to pass urine, changes in urine output, blood in the urine, or sudden weight gain.
Electrolyte Imbalance: Mood changes, confusion, muscle pain, cramps, or spasms, weakness, shakiness, balance problems, abnormal heartbeat, seizures, loss of appetite, or severe nausea and vomiting.
High Blood Pressure: Severe headache or dizziness, fainting, or changes in vision.
Acidosis (Too Much Acid in the Blood): Confusion, rapid breathing, rapid heartbeat, irregular heartbeat, severe stomach pain, nausea, vomiting, excessive sleepiness, shortness of breath, or extreme fatigue and weakness.
Skin Problems: Warm, red, or painful skin or sores on the body.
Chest Pain or Shortness of Breath: Chest pain or pressure, shortness of breath, sudden weight gain, or swelling in the arms or legs.
Neurological Symptoms: Shakiness, difficulty moving, unexplained bruising or bleeding, burning, numbness, or tingling sensations, or pale skin.
Progressive Multifocal Leukoencephalopathy (PML): A rare and potentially fatal brain condition. Seek medical help if you experience confusion, memory problems, depression, changes in behavior, weakness on one side of the body, speech or thinking difficulties, balance problems, or vision changes.
Posterior Reversible Encephalopathy Syndrome (PRES): A rare and potentially life-threatening brain condition. Seek medical help if you experience confusion, decreased alertness, vision changes, loss of vision, seizures, or severe headache.
Abnormal Heartbeat (Prolonged QT Interval): This medication may increase the risk of other potentially life-threatening abnormal heartbeats.
Gastrointestinal Problems: Severe stomach pain, black, tarry, or bloody stools, vomiting blood, or coffee ground-like vomit.
Blood Problems: Thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS), a rare and potentially life-threatening condition. Seek medical help if you experience confusion, extreme fatigue, bruising, bleeding, dark urine, yellow skin or eyes, pale skin, changes in urine output, vision changes, weakness on one side of the body, speech or thinking difficulties, balance problems, or fever.
Other Possible Side Effects
Most people do not experience severe side effects, but some may occur. If you notice any of the following symptoms, contact your doctor or seek medical attention if they bother you or do not go away:
Dizziness, fatigue, or weakness
Headache
Constipation, diarrhea, stomach pain, nausea, vomiting, or decreased appetite
Heartburn
Sleep disturbances
Back pain
Joint pain
* Nose or throat irritation
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.
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 medical attention immediately:
Allergic Reaction: 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; or swelling of the mouth, face, lips, tongue, or throat.
Kidney Problems: Inability to pass urine, changes in urine output, blood in the urine, or sudden weight gain.
Electrolyte Imbalance: Mood changes, confusion, muscle pain, cramps, or spasms, weakness, shakiness, balance problems, abnormal heartbeat, seizures, loss of appetite, or severe nausea and vomiting.
High Blood Pressure: Severe headache or dizziness, fainting, or changes in vision.
Acidosis (Too Much Acid in the Blood): Confusion, rapid breathing, rapid heartbeat, irregular heartbeat, severe stomach pain, nausea, vomiting, excessive sleepiness, shortness of breath, or extreme fatigue and weakness.
Skin Problems: Warm, red, or painful skin or sores on the body.
Chest Pain or Shortness of Breath: Chest pain or pressure, shortness of breath, sudden weight gain, or swelling in the arms or legs.
Neurological Symptoms: Shakiness, difficulty moving, unexplained bruising or bleeding, burning, numbness, or tingling sensations, or pale skin.
Progressive Multifocal Leukoencephalopathy (PML): A rare and potentially fatal brain condition. Seek medical help if you experience confusion, memory problems, depression, changes in behavior, weakness on one side of the body, speech or thinking difficulties, balance problems, or vision changes.
Posterior Reversible Encephalopathy Syndrome (PRES): A rare and potentially life-threatening brain condition. Seek medical help if you experience confusion, decreased alertness, vision changes, loss of vision, seizures, or severe headache.
Abnormal Heartbeat (Prolonged QT Interval): This medication may increase the risk of other potentially life-threatening abnormal heartbeats.
Gastrointestinal Problems: Severe stomach pain, black, tarry, or bloody stools, vomiting blood, or coffee ground-like vomit.
Blood Problems: Thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS), a rare and potentially life-threatening condition. Seek medical help if you experience confusion, extreme fatigue, bruising, bleeding, dark urine, yellow skin or eyes, pale skin, changes in urine output, vision changes, weakness on one side of the body, speech or thinking difficulties, balance problems, or fever.
Other Possible Side Effects
Most people do not experience severe side effects, but some may occur. If you notice any of the following symptoms, contact your doctor or seek medical attention if they bother you or do not go away:
Dizziness, fatigue, or weakness
Headache
Constipation, diarrhea, stomach pain, nausea, vomiting, or decreased appetite
Heartburn
Sleep disturbances
Back pain
Joint pain
* Nose or throat irritation
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:
- Signs of infection: fever, chills, sore throat, cough, unusual fatigue, painful urination, new skin lesions.
- Neurological symptoms: severe headache, tremor, numbness or tingling, confusion, seizures, vision changes.
- Kidney problems: swelling in legs/ankles, decreased urination, unusual fatigue.
- Liver problems: yellowing of skin/eyes (jaundice), dark urine, severe nausea/vomiting, abdominal pain.
- High blood sugar: increased thirst, frequent urination, increased hunger, blurred vision.
- High blood pressure: severe headache, blurred vision.
- Unusual bleeding or bruising.
- New lumps or growths on your body.
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.
If you have a prolonged QT interval on an electrocardiogram (ECG).
If you are currently taking cyclosporine or sirolimus.
If you or your partner are pregnant, as this medication may harm the unborn baby.
If you or your partner plan to become pregnant, discuss effective birth control methods with your doctor before starting this medication. If you or your partner become pregnant while taking this medication, notify your doctor immediately.
If you are breastfeeding or plan to breastfeed.
This medication can interact with other drugs and health conditions. Therefore, it is crucial to provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter medications you are taking
Any natural products or vitamins you are using
* Your health problems
Your doctor will help you determine whether it is safe to take this medication with your other medications and health conditions. Do not start, stop, or change the dose of any medication without first consulting 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.
If you have a prolonged QT interval on an electrocardiogram (ECG).
If you are currently taking cyclosporine or sirolimus.
If you or your partner are pregnant, as this medication may harm the unborn baby.
If you or your partner plan to become pregnant, discuss effective birth control methods with your doctor before starting this medication. If you or your partner become pregnant while taking this medication, notify your doctor immediately.
If you are breastfeeding or plan to breastfeed.
This medication can interact with other drugs and health conditions. Therefore, it is crucial to provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter medications you are taking
Any natural products or vitamins you are using
* Your health problems
Your doctor will help you determine whether it is safe to take this medication with your other medications and health conditions. Do not start, stop, or change the dose of any medication without first consulting your doctor.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. When you receive a new prescription, verify that you have the correct medication by checking it carefully. If you suspect that you have been given the wrong medication or are unsure about its appearance, contact your doctor immediately.
To minimize the risk of infection, practice good hygiene by washing your hands frequently and avoid close contact with individuals who have infections, colds, or flu.
Regular blood tests and other laboratory evaluations are crucial while taking this medication, as directed by your doctor. Many other medications can interact with this drug, potentially increasing the risk of organ rejection or side effects. If you are taking other medications, consult with your doctor to determine if more frequent blood tests are necessary.
If you are using a salt substitute containing potassium, a potassium-sparing diuretic, or a potassium product, discuss this with your doctor. Additionally, avoid consuming grapefruit and grapefruit juice while taking this medication.
Monitor your blood pressure regularly, as this medication can cause high blood pressure. Your doctor will advise you on the frequency of blood pressure checks.
This medication can also cause high blood sugar levels, including new-onset or worsening diabetes. Check your blood sugar levels as instructed by your doctor, and report any symptoms of high blood sugar, such as confusion, drowsiness, increased thirst or hunger, frequent urination, flushing, rapid breathing, or fruity-smelling breath.
Ensure that you are up to date with all recommended vaccinations before starting treatment with this medication. Consult with your doctor before receiving any vaccines, as some vaccines may not be effective or may increase the risk of infection when taken with this medication.
Prolonged exposure to sunlight, sunlamps, or tanning beds can increase the risk of skin cancer while taking this medication. Protect yourself from the sun by using sunscreen, wearing protective clothing, and eyewear.
This medication may affect fertility, potentially leading to difficulty conceiving or fathering a child. If you plan to become pregnant or father a child, discuss this with your doctor before initiating treatment with this medication.
To minimize the risk of infection, practice good hygiene by washing your hands frequently and avoid close contact with individuals who have infections, colds, or flu.
Regular blood tests and other laboratory evaluations are crucial while taking this medication, as directed by your doctor. Many other medications can interact with this drug, potentially increasing the risk of organ rejection or side effects. If you are taking other medications, consult with your doctor to determine if more frequent blood tests are necessary.
If you are using a salt substitute containing potassium, a potassium-sparing diuretic, or a potassium product, discuss this with your doctor. Additionally, avoid consuming grapefruit and grapefruit juice while taking this medication.
Monitor your blood pressure regularly, as this medication can cause high blood pressure. Your doctor will advise you on the frequency of blood pressure checks.
This medication can also cause high blood sugar levels, including new-onset or worsening diabetes. Check your blood sugar levels as instructed by your doctor, and report any symptoms of high blood sugar, such as confusion, drowsiness, increased thirst or hunger, frequent urination, flushing, rapid breathing, or fruity-smelling breath.
Ensure that you are up to date with all recommended vaccinations before starting treatment with this medication. Consult with your doctor before receiving any vaccines, as some vaccines may not be effective or may increase the risk of infection when taken with this medication.
Prolonged exposure to sunlight, sunlamps, or tanning beds can increase the risk of skin cancer while taking this medication. Protect yourself from the sun by using sunscreen, wearing protective clothing, and eyewear.
This medication may affect fertility, potentially leading to difficulty conceiving or fathering a child. If you plan to become pregnant or father a child, discuss this with your doctor before initiating treatment with this medication.
Overdose Information
Overdose Symptoms:
- Severe tremor
- Headache
- Nausea, vomiting
- Diarrhea
- Kidney dysfunction (elevated creatinine)
- Liver dysfunction
- Neurotoxicity (e.g., seizures, encephalopathy)
- Hyperkalemia
What to Do:
There is no specific antidote for tacrolimus overdose. Treatment is supportive. Contact a poison control center or emergency medical services immediately. Call 1-800-222-1222.
Drug Interactions
Contraindicated Interactions
- Live attenuated vaccines (due to immunosuppression)
- Pimecrolimus, Sirolimus, Everolimus (additive immunosuppression, increased risk of toxicity)
- Strong CYP3A4/5 inhibitors (e.g., ketoconazole, itraconazole, voriconazole, clarithromycin, ritonavir, grapefruit juice) - significantly increase tacrolimus levels, leading to toxicity.
- Strong CYP3A4/5 inducers (e.g., rifampin, phenytoin, carbamazepine, St. John's Wort) - significantly decrease tacrolimus levels, leading to rejection.
Major Interactions
- Nephrotoxic agents (e.g., NSAIDs, aminoglycosides, amphotericin B, cyclosporine) - increased risk of nephrotoxicity.
- Potassium-sparing diuretics, ACE inhibitors, ARBs (increased risk of hyperkalemia).
- Vaccines (reduced efficacy of inactivated vaccines).
- Other immunosuppressants (e.g., mycophenolate mofetil, azathioprine, corticosteroids) - increased risk of infection and malignancy.
- Diltiazem, Verapamil, Amiodarone, Erythromycin (moderate CYP3A4 inhibitors - increase tacrolimus levels).
- Phenobarbital, Isoniazid, Efavirenz (moderate CYP3A4 inducers - decrease tacrolimus levels).
Moderate Interactions
- Oral contraceptives (may affect tacrolimus levels, monitor).
- Magnesium/aluminum hydroxide antacids (may decrease tacrolimus absorption).
- Metoclopramide (may increase tacrolimus absorption).
- Cannabidiol (CBD) - potential CYP3A4 inhibition, monitor tacrolimus levels.
Minor Interactions
- Not specifically categorized as minor, as most interactions are clinically significant due to narrow therapeutic index.
Monitoring
Baseline Monitoring
Complete Blood Count (CBC) with differential
Rationale: To establish baseline hematologic parameters and monitor for potential myelosuppression.
Timing: Prior to initiation
Renal function (serum creatinine, BUN, eGFR)
Rationale: To establish baseline kidney function and monitor for tacrolimus-induced nephrotoxicity.
Timing: Prior to initiation
Liver function tests (ALT, AST, ALP, bilirubin)
Rationale: To establish baseline liver function and monitor for potential hepatotoxicity.
Timing: Prior to initiation
Electrolytes (potassium, magnesium, phosphorus)
Rationale: To establish baseline levels and monitor for hyperkalemia, hypomagnesemia, hypophosphatemia.
Timing: Prior to initiation
Blood pressure
Rationale: To establish baseline and monitor for hypertension.
Timing: Prior to initiation
Blood glucose
Rationale: To establish baseline and monitor for new-onset diabetes after transplant (NODAT).
Timing: Prior to initiation
Routine Monitoring
Tacrolimus whole blood trough levels
Frequency: Initially 2-3 times per week until stable, then weekly for the first month, then every 1-3 months or as clinically indicated.
Target: Highly variable based on transplant type, time post-transplant, and concomitant immunosuppression (e.g., 5-15 ng/mL for kidney/liver, 8-20 ng/mL for heart, often lower long-term).
Action Threshold: Levels outside target range require dose adjustment and re-monitoring.
Renal function (serum creatinine, BUN, eGFR)
Frequency: Weekly for the first month, then monthly or as clinically indicated.
Target: Stable, within acceptable post-transplant range.
Action Threshold: Significant increase in creatinine (>25% from baseline or rising trend) may indicate nephrotoxicity or rejection, requiring investigation and potential dose adjustment.
Electrolytes (potassium, magnesium)
Frequency: Weekly for the first month, then monthly or as clinically indicated.
Target: Potassium 3.5-5.0 mEq/L, Magnesium 1.5-2.5 mg/dL.
Action Threshold: Hyperkalemia (>5.5 mEq/L) or hypomagnesemia (<1.5 mg/dL) may require intervention or dose adjustment.
Blood pressure
Frequency: Regularly (e.g., daily in inpatient, weekly/monthly in outpatient).
Target: <130/80 mmHg (or as per guideline).
Action Threshold: Sustained hypertension requires antihypertensive therapy or tacrolimus dose adjustment.
Blood glucose
Frequency: Weekly for the first month, then monthly or as clinically indicated.
Target: Fasting <100 mg/dL, HbA1c <6.5%.
Action Threshold: Elevated glucose levels may indicate NODAT, requiring management.
CBC with differential
Frequency: Monthly or as clinically indicated.
Target: Within normal limits.
Action Threshold: Significant leukopenia, anemia, or thrombocytopenia may require investigation and dose adjustment.
Symptom Monitoring
- Signs of infection (fever, chills, sore throat, unusual fatigue, new pain)
- Signs of malignancy (new lumps, unexplained weight loss, persistent fatigue)
- Neurological symptoms (headache, tremor, seizures, confusion, paresthesias, visual disturbances)
- Renal dysfunction (decreased urine output, swelling in legs/ankles, fatigue)
- Gastrointestinal symptoms (nausea, vomiting, diarrhea, abdominal pain)
- Cardiovascular symptoms (chest pain, palpitations, shortness of breath, swelling)
- Skin changes (rash, itching, skin lesions)
Special Patient Groups
Pregnancy
Tacrolimus is generally considered Category C (some sources may list D due to potential risks). It crosses the placenta and has been associated with adverse fetal outcomes, including premature birth, low birth weight, hyperkalemia, and renal dysfunction in the neonate. However, the benefits of preventing organ rejection in the mother often outweigh the risks, and tacrolimus is often continued during pregnancy with close monitoring of maternal tacrolimus levels and fetal well-being.
Trimester-Specific Risks:
First Trimester:
Potential for congenital anomalies, though data are mixed and not consistently higher than general population. Close monitoring is crucial.
Second Trimester:
Risk of premature birth, low birth weight, and potential for fetal renal dysfunction and hyperkalemia. Close monitoring of fetal growth and renal function is recommended.
Third Trimester:
Continued risk of premature birth, low birth weight, and neonatal renal dysfunction/hyperkalemia. Neonatal monitoring for these issues is essential post-delivery.
Lactation
Tacrolimus is excreted into breast milk. Due to the potential for serious adverse effects in the nursing infant (e.g., immunosuppression, nephrotoxicity, neurotoxicity), breastfeeding is generally not recommended while taking tacrolimus. The decision should be made considering the importance of the drug to the mother and the potential risks to the infant.
Infant Risk:
L5 (Contraindicated/High Risk) - Potential for serious adverse effects in the infant.
Pediatric Use
Pediatric patients, especially younger children, generally require higher doses per kilogram compared to adults due to faster drug clearance. Dosing must be highly individualized and guided by therapeutic drug monitoring. They are also at increased risk for post-transplant lymphoproliferative disorder (PTLD) and other infections.
Geriatric Use
No specific dose adjustments are typically required based solely on age, but geriatric patients may have age-related decreases in renal or hepatic function, which could necessitate dose adjustments. They may also be more susceptible to adverse effects such, as neurotoxicity and nephrotoxicity. Close monitoring of tacrolimus levels and adverse effects is crucial.
Clinical Information
Clinical Pearls
- Tacrolimus has a narrow therapeutic index; therapeutic drug monitoring (TDM) of whole blood trough levels is essential for safe and effective use.
- Consistency is key: Administer at the same time each day, and consistently with or without food (preferably without food) to minimize variability in absorption.
- Avoid grapefruit products and St. John's Wort due to significant drug interactions.
- Patients should be educated on the signs and symptoms of infection, malignancy, nephrotoxicity, and neurotoxicity.
- Tacrolimus can cause new-onset diabetes after transplant (NODAT) and hypertension; monitor blood glucose and blood pressure regularly.
- Hypomagnesemia is a common side effect; magnesium supplementation may be required.
- Different formulations (immediate-release vs. extended-release) and even different brands of tacrolimus are NOT interchangeable on a milligram-to-milligram basis. Any switch requires careful physician supervision and re-monitoring of levels.
Alternative Therapies
- Cyclosporine (another calcineurin inhibitor)
- Sirolimus (mTOR inhibitor)
- Everolimus (mTOR inhibitor)
- Belatacept (selective T-cell costimulation blocker)
- Mycophenolate mofetil (antimetabolite)
- Azathioprine (antimetabolite)
Cost & Coverage
Average Cost:
Varies widely by pharmacy, formulation, and quantity (e.g., $100-$1000+) per 30 capsules
Generic Available:
Yes
Insurance Coverage:
Tier 3 or Specialty Tier (often requires prior authorization)
General Drug Facts
If your symptoms or health issues persist or worsen, it is 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 it's a good idea to check with your pharmacist. If you have any questions or concerns about this 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 detailed information about the overdose, including the medication taken, the amount, and the time it occurred.