Specialty Drug
FENTANYL is a pain reliever. It is used to treat breakthrough cancer pain that your long acting pain medicine does not control. Do not use this medicine for a pain that will go away in a few days like pain from surgery, doctor or dentist visits. The medicine is used only by people who have been taking an opioid or narcotic pain medicine for at least a week. Compare opioids.

Lazanda Side Effects

What should I watch for?

Tell your doctor or health care professional if your pain does not go away, if it gets worse, or if you have new or a different type of pain. You may develop tolerance to the medicine. Tolerance means that you will need a higher dose of the medicine for pain relief. Tolerance is normal and is expected if you take the medicine for a long time.

Do not suddenly stop taking your medicine because you may develop a severe reaction. Your body becomes used to the medicine. This does NOT mean you are addicted. Addiction is a behavior related to getting and using a drug for a non-medical reason. If you have pain, you have a medical reason to take pain medicine. Your doctor will tell you how much medicine to take. If your doctor wants you to stop the medicine, the dose will be slowly lowered over time to avoid any side effects.

There are different types of narcotic medicines (opiates). If you take more than one type at the same time or you are taking another medicine that also causes drowsiness, you may have more side effects. Give your health care provider a list of all medicines you use. Your doctor will tell you how much medicine to take. Do not take more medicine than directed. Call emergency for help if you have problems breathing or unusual sleepiness.

You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol may interfere with the effect of this medicine. Avoid alcoholic drinks.

This medicine will cause constipation. Try to have a bowel movement at least every 2 to 3 days. If you do not have a bowel movement for 3 days, call your doctor or health care professional.

Your mouth may get dry. Chewing sugarless gum or sucking hard candy, and drinking plenty of water may help. Contact your doctor if the problem does not go away or is severe.


Interactions with Medications

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common


Less common

Abdominal or stomach pain


black, tarry stools

bladder pain

bloating or swelling of the face, arms, hands, lower legs, or feet

bloody nose

bloody or cloudy urine

blurred vision

body aches or pain

chest pain


clay-colored stools



cough producing mucus

dark urine

decreased urination

decreased weight

difficult or labored breathing

difficult, burning, or painful urination

difficulty with breathing

dizziness or lightheadedness

dry mouth

ear congestion


frequent urge to urinate




increase in heart rate

increased sweating



joint pain, stiffness, or swelling

loss of appetite

loss of voice

lower back or side pain



pain, redness, or swelling in the arm or leg

pale skin

pounding in the ears

rapid breathing

rapid weight gain


redness of the skin

runny or stuffy nose

shortness of breath

slow or fast heartbeat


sore throat

sudden shortness of breath or troubled breathing

sunken eyes

swelling of the eyelids, face, lips, hands, or feet


tightness in the chest

tingling of the hands or feet

troubled breathing or swallowing

troubled breathing with exertion

ulcers, sores, or white spots in the mouth

unpleasant breath odor

unusual bleeding or bruising

unusual tiredness or weakness

unusual weight gain or loss

vomiting of blood


wrinkled skin

yellow eyes or skin

Incidence not known

Irregular, fast or slow, or shallow breathing

pale or blue lips, fingernails, or skin

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

Difficulty having a bowel movement (stool)

sleepiness or unusual drowsiness


Less common

Acid or sour stomach

back pain


burning feeling in the chest or stomach

change in taste

confusion about identity, place, and time

decreased appetite



difficulty with moving

drooping upper eyelids

dry eyes

flushed, dry skin

fruit-like breath odor



increased hunger

increased thirst

increased urination


irregular heartbeats


irritation or soreness of the mouth

lack or loss of strength

loss of taste

muscle aches

muscle pain or stiffness

pain in the arms or legs

pain in the rectum




stomach discomfort or upset

stomach bloating


tenderness in the stomach area

trouble with sleeping

troubled breathing

unable to sleep

unexplained weight loss

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

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