SIDE EFFECTS: See also Warning section. Shaking, headache, diarrhea, nausea/vomiting, upset stomach, loss of appetite, trouble sleeping, and numbness/tingling of the hands/feet may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly. Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. Tell your doctor right away if you have any serious side effects, including: mental/mood changes, dizziness, signs of kidney problems (such as change in the amount of urine), pounding heartbeat, symptoms of heart failure (such as shortness of breath, swelling ankles/feet, unusual tiredness, unusual/sudden weight gain), hearing problems (such as hearing loss, ringing in the ears), pain/redness/swelling of arms or legs, easy bruising/bleeding, muscle pain/cramp/weakness, yellowing skin/eyes, dark urine, persistent nausea/vomiting, severe stomach/abdominal pain, severe leg pain. This medication may also increase your risk of getting a rare but very serious (sometimes fatal) brain infection (progressive multifocal leukoencephalopathy-PML). Get medical help right away if any of these rare but very serious side effects occur: clumsiness, loss of coordination, weakness, sudden change in your thinking (such as confusion, difficulty concentrating), difficulty moving your muscles, problems with speech, seizure, vision changes. Get medical help right away if you have any very serious side effects, including: fainting, fast/irregular heartbeat, severe dizziness, chest/jaw/left arm pain, black stools, vomit that looks like coffee grounds. This medication may raise your blood pressure. Check your blood pressure regularly and tell your doctor if the results are high. Your doctor may control your blood pressure with medication. Tacrolimus may cause diabetes. Tell your doctor or pharmacist if you experience any of the following symptoms of high blood sugar: increased thirst/hunger, frequent urination. A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing. This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist. In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch. In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

PRECAUTIONS: Before taking tacrolimus, tell your doctor or pharmacist if you are allergic to it; or to other macrolide medications (such as sirolimus); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details. Before using this medication, tell your doctor or pharmacist your medical history, especially of: mineral imbalances (such as high potassium), kidney disease, any recent/current infections, cancer, liver disease, high blood pressure, diabetes. Tacrolimus may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can rarely cause serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away. The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may cause QT prolongation. Before using tacrolimus, tell your doctor or pharmacist of all the drugs you take and if you have any of the following conditions: certain heart problems (heart failure, slow heartbeat, QT prolongation in the EKG), family history of certain heart problems (QT prolongation in the EKG, sudden cardiac death). Low levels of potassium or magnesium in the blood may also increase your risk of QT prolongation. This risk may increase if you use certain drugs (such as diuretics/"water pills") or if you have conditions such as severe sweating, diarrhea, or vomiting. Talk to your doctor about using tacrolimus safely. This medication may increase your risk of developing skin cancer. Limit your time in the sun. Avoid tanning booths and sunlamps. Use sunscreen and wear protective clothing when outdoors. Tacrolimus can make you more likely to get infections or may worsen any current infections. Therefore, wash your hands well to prevent the spread of infection. Avoid contact with people who have infections that may spread to others (such as chickenpox, measles, flu). Consult your doctor if you have been exposed to an infection or for more details. Do not have immunizations/vaccinations without the consent of your doctor. Avoid contact with people who have recently received live vaccines (such as flu vaccine inhaled through the nose). This drug may increase your potassium levels. Before using potassium supplements or salt substitutes containing potassium, consult your doctor or pharmacist. Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products). Older adults may be more sensitive to the side effects of this drug, especially QT prolongation (see above). Since this drug can be absorbed through the skin and lungs and may harm an unborn baby, women who are pregnant or who may become pregnant should not handle this medication or breathe the dust from the capsules. Tell your doctor if you are pregnant or plan to become pregnant. You should not become pregnant while using tacrolimus. Tacrolimus may harm an unborn baby. Men and women using this medication should ask about reliable forms of birth control before and while using this medication. If you or your partner become pregnant, talk to your doctor right away about the risks and benefits of this medication. Do not stop taking this medication unless directed by your doctor. This drug passes into breast milk and the effect on a nursing infant is unknown. Discuss the risks and benefits with your doctor before breast-feeding.

DRUG INTERACTIONS: See also How to Use section. Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval. Some products that may interact with this drug include: aluminum/magnesium antacid, cyclosporine, sirolimus, temsirolimus, ziprasidone, other drugs that may increase the level of potassium in the blood (such as "water pills" including amiloride, spironolactone), other drugs that weaken the immune system/increase the risk of infection (such as natalizumab, rituximab). Other medications can affect the removal of tacrolimus from your body, which may affect how tacrolimus works. Examples include cimetidine, danazol, nefazodone, ethinyl estradiol, methylprednisolone, St. John's wort, azole antifungals (such as itraconazole, voriconazole), HIV and HCV protease inhibitors (such as nelfinavir, ritonavir, boceprevir, telaprevir), rifamycins (such as rifampin, rifabutin), certain anti-seizure drugs (such as phenobarbital, phenytoin), among others.

OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.