Fentanyl Injection

Instructions

Drug interactions can change how medicines work or increase risk for side effects. Tell your health care providers about all medicines taken. Include prescription and over-the-counter medicines, vitamins, and herbal medicines. Speak with your doctor or pharmacist before starting or stopping any medicine.

Tell your doctor if symptoms do not get better or if they get worse.

To reduce constipation, eat high fiber foods, drink plenty of water and exercise.

Cautions

This medicine has an opioid. Opioids help many people but may cause addiction, especially if used for a long time. The addiction risk is higher if you have a substance use disorder (overuse of or addiction to drugs or alcohol). Ask your doctor about the benefits and risks.

Ask your doctor or pharmacist if you should have naloxone on hand to treat opioid overdose. Teach your family or household members about the signs of an opioid overdose and how to treat it.

If you stop this medicine suddenly after using it for a long time, you may have withdrawal. Your doctor may slowly lower your dose before stopping it. Tell your doctor right away if you have symptoms, such as unusual sweating, watering eyes, runny nose, chills, diarrhea, yawning, muscle aches, restlessness, anxiety, trouble sleeping, or thoughts of suicide.

Tell your doctor and pharmacist if you ever had an allergic reaction to a medicine.

Some patients taking this medicine have experienced serious side effects. Please speak with your doctor to understand the risks and benefits associated with this medicine.

Your ability to stay alert or to react quickly may be impaired by this medicine. Do not drive or operate machinery until you know how this medicine will affect you.

If possible, avoid using with alcohol, marijuana, or other medicines that can cause dizziness or drowsiness. These include allergy/cold products, muscle relaxers, sleep aids, and pain relievers.

This medicine passes into breast milk. Ask your doctor before breastfeeding.

This medicine can hurt a new baby in the womb. If you become pregnant while on this medicine, tell your doctor immediately. Your doctor may switch you to a different medicine.

This medicine should be used with caution in patients with breathing difficulties.

Call your doctor right away if you notice slow or shallow breathing.

Side Effects

The following is a list of some common side effects from this medicine. Please speak with your doctor about what you should do if you experience these or other side effects.

• agitated feeling or trouble sleeping
• decreased appetite
• constipation
• dizziness or drowsiness
• headaches
• pain, redness, swelling near injection
• lightheadedness
• nausea and vomiting
• stomach upset or abdominal pain

If you have any of the following side effects, you may be getting too much medicine. Please contact your doctor to let them know about these side effects.

• fainting
• hallucinations (unusual thoughts, seeing or hearing things that are not real)
• severe stomach or bowel pain

Call your doctor or get medical help right away if you notice any of these more serious side effects:

• decreased awareness or responsiveness
• breathing interruption during sleep
• shallow, irregular breathing
• confusion
• fast, irregular, or slow heartbeat
• muscle trembling
• seizures
• unusual or unexplained tiredness or weakness
• difficulty or discomfort urinating
• weight loss

A few people may have an allergic reaction to this medicine. Symptoms can include difficulty breathing, skin rash, itching, swelling, or severe dizziness. If you notice any of these symptoms, seek medical help quickly.