Arsenic trioxide (Trisenox) is an anticancer medication used to treat a rare type of cancer of the blood cells called acute promyelocytic leukemia (APL). It’s given as a slow injection into the vein (intravenous, IV) at an infusion center or clinic once a day for several months of treatment. Arsenic trioxide (Trisenox) is sometimes given along with tretinoin (all-trans retinoic acid (ATRA)) to treat certain types of APL. The medication can cause side effects such as nausea, heart rhythm changes, and a serious condition called differentiation syndrome. Both the brand-name medication Trisenox and the generic are available.
Refractory or relapsed acute promyelocytic leukemia (APL) in children and adults who have previously been treated with a retinoid and anthracycline chemotherapy
Newly diagnosed, low-risk acute promyelocytic leukemia (APL) in adults, given together with tretinoin (all-trans retinoic acid (ATRA))
Acute promyelocytic leukemia (APL) is caused by a genetic change which signals young white blood cells to divide and grow before they’re fully mature. With too many immature blood cells in your body. This leads to lower amounts of healthy blood cells and platelets in your body.
Arsenic trioxide (Trisenox) damages the abnormal protein created by the genetic change that causes APL. This results in young white blood cells growing and maturing into healthy cells.
Arsenic trioxide (Trisenox) also helps by causing cancer cells to die faster.
Source: DailyMed
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 or nurse immediately if any of the following side effects occur:
More common
Chills
decreased urine output
general feeling of illness
headache
increased thirst
irregular heartbeat
loss of appetite
mood changes
muscle pain or cramps
numbness or tingling in hands, feet, or lips
seizures
trouble breathing
unusual tiredness or weakness
vomiting
Less common
Black, tarry stools
bluish lips or skin
blurred vision
dizziness or lightheadedness
flushed, dry skin
fruit-like breath odor
increased hunger
increased urine output
irregular or pounding heartbeat or pulse
painful or difficult urination
sores, ulcers, or white spots on the lips or in the mouth
stomach ache or cramps
sweating
swollen glands
unexplained weight loss
unusual bleeding or bruising
unusual weight gain
Incidence not known
Agitation
back pain
behavior changes similar to drunkenness
blistering, peeling, or loosening of the skin
blood in the urine or stools
bluish fingernails, palms, or nailbeds
bruising
change in size, shape, or color of existing mole
cloudy urine
cold sweats
cool, pale skin
confusion
coughing that sometimes produces a pink frothy sputum
coughing or spitting up blood
dark urine
difficult, fast, noisy breathing
dilated neck veins
drowsiness
extreme tiredness or weakness
fainting
fast heartbeat
high fever
indigestion
irregular heartbeat, recurrent
irritability
joint pain
large hives, itching, or skin rash
loss of consciousness
mole that leaks fluid or bleeds new mole
painful blisters on the trunk of the body
pains in the stomach, side, or abdomen, possibly radiating to the back
pale skin
persistent bleeding or oozing from puncture sites, mouth, or nose
rapid, shallow breathing
red skin lesions, often with a purple center
red, irritated eyes
seeing, hearing, or feeling things that are not there
severe nausea
shakiness
stiff neck
sudden weight gain
tightness in the chest
swelling of the eyelids, lips, face, fingers, or lower legs
unsteadiness or awkwardness
vomiting of blood or material that looks like coffee grounds
yellow eyes or skin
Get emergency help immediately if any of the following symptoms of overdose occur:
Symptoms of overdose
Confusion
muscle weakness, severe
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:
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.
Recommended first-choice treatment of APL in combination with tretinoin (ATRA)
Works in a more targeted way in people with APL
Typically doesn’t cause hair loss
Requires daily infusions for several months, so less convenient
Requires regular electrocardiograms (EKGs) to monitor for heart rhythm changes
Might cause a serious side effect called differentiation syndrome
Arsenic trioxide (Trisenox) is given slowly, typically over 2 hours. In some instances, it might even take up to 4 hours. So plan accordingly for this time. Make sure you dress comfortably, bring water and food, and have something to help you pass the time, such as a book or music.
Arsenic trioxide (Trisenox) might cause nausea, and your oncologist could recommend antiemetic medications to help prevent and treat it. But they might advise against certain ones like ondansetron (Zofran), which can cause QT prolongation. Because arsenic trioxide (Trisenox) can also cause QT prolongation, taking both medications could raise this risk. Talk to your oncologist about which medications are safe for you to take.
You might experience some diarrhea while taking arsenic trioxide (Trisenox). Your oncologist might suggest an over-the-counter medication like loperamide (Imodium A-D) to help manage diarrhea. Contact your oncologist right away if you have signs of dehydration such as dry skin and urinating less often, as dehydration can lower your blood electrolyte levels. And reduced electrolytes can raise your risk of heart problems with arsenic trioxide (Trisenox).
Taking arsenic trioxide (Trisenox) can sometimes irritate your liver, sometimes without noticeable symptoms. Regular blood tests, sometimes done multiple times a week, are important to check your liver health while on this medication. If you experience stomach pain or yellowing of the skin or whites of your eyes, contact your oncologist right away.
People taking arsenic trioxide (Trisenox) and who have low levels of a vitamin called thiamine might be at higher risk for a nervous system problem called Wernicke’s encephalopathy. Symptoms include confusion, fatigue, and muscle coordination problems. If you’re at risk for this side effect, your oncologist will likely check your thiamine levels.
If you’re a male, arsenic trioxide (Trisenox) might affect your ability to have children. Talk with your oncologist if you have questions about this potential risk.
Arsenic trioxide (Trisenox) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Differentiation syndrome is a serious complication that can happen with APL treatments like arsenic trioxide (Trisenox). It’s an immune response that leads to small proteins called cytokines becoming active and causing problems in the body. Symptoms include fever, fluid build-up and swelling in the lower legs, sudden weight gain, and trouble breathing.
It can happen as early as the first day of the induction phase or as late as the second month of the induction phase. Treatment usually includes corticosteroids such as dexamethasone, and you might also need medications to help keep your blood pressure in a normal range. If your symptoms are severe, you might need to stop treatment with arsenic trioxide (Trisenox). Once differentiation syndrome improves, you can typically restart the medication.
Risk factors: Heart failure | Heart rhythm problems | Taking Arsenic trioxide (Trisenox) with other medications that can change heart rhythm | Low magnesium or potassium levels in the blood
Some people taking arsenic trioxide (Trisenox) have changes in their heart rhythm. QT prolongation is the most common and was seen in studies to happen between 1 and 5 weeks after starting the medication. Some symptoms include lightheadedness, irregular heartbeat, blurry vision, and fainting.
Because it doesn’t always cause symptoms, the best way for your oncologist to monitor this side effect is through a test called an electrocardiogram (ECG or EKG). You’ll need an EKG before you start taking arsenic trioxide (Trisenox) and once a week during treatment. Low levels of potassium and magnesium in your blood can raise your risk of QT prolongation, so your oncologist will also monitor these closely with lab tests. If you develop long QT, you might need to pause arsenic trioxide (Trisenox) while your oncologist looks into it.
Risk factors: Low thiamine levels | Long-term alcohol use | Gut absorption problems | Nutritional deficiency | Taking arsenic trioxide (Trisenox) with furosemide (Lasix)
Some people taking Arsenic trioxide (Trisenox) have developed nervous system problems called encephalopathy. Symptoms include confusion, trouble staying awake, seizures, trouble speaking, and vision changes. It’s important for family members and caregivers to be aware of this possible side effect, because someone experiencing these symptoms might not be able to describe what’s wrong.
A specific type of encephalopathy called Wernicke’s encephalopathy has also occurred with arsenic trioxide (Trisenox) treatment, and this can be treated with a vitamin called thiamine. If you have low thiamine, which can happen if you have gut absorption problems or drink alcohol often, talk to your oncologist before you start taking this medication. Your oncologist can test your thiamine level with a lab test.
Sometimes, arsenic trioxide (Trisenox) treatment can cause liver problems. Most of the time, when your liver is irritated you won't feel any noticeable symptoms. But your oncologist can see signs of this through blood tests. Make sure you get regular blood tests while you're taking arsenic trioxide (Trisenox) so your oncologist can check your liver health and make sure it's still safe for you to take. If you have stomach pain, yellowish skin, or yellow around the whites of your eyes, call your oncologist right away. If your lab tests show liver irritation, you might need to pause arsenic trioxide (Trisenox) or take a lower dose.
Arsenic trioxide (Trisenox) is a known carcinogen, which means it can cause cancer. Your oncologist will regularly check you for signs and symptoms of new cancers even after your treatment with arsenic trioxide (Trisenox) is complete.
There haven’t been studies of arsenic trioxide (Trisenox) in human pregnancy, but based on animal studies and the way the medication works, it could cause harm to an unborn baby. If you’re able to have children, you use effective birth control while taking arsenic trioxide (Trisenox) and for 6 months after the last dose. If you’re a male who is sexually active with a partner who can have children, use birth control such as condoms while taking arsenic trioxide (Trisenox) and for 3 months after the last dose. Contact your oncologist right away if you become pregnant while taking arsenic trioxide (Trisenox).
The recommended dose depends on the treatment phase (induction or consolidation).
Refractory or relapsed APL
Induction: The typical dose is 0.15 mg/kg of bodyweight, injected into a vein once a day until bone marrow remission or for up to 60 days.
Consolidation: The typical dose is 0.15 mg/kg of bodyweight, injected into a vein once a day for 25 doses over 5 weeks
Consolidation begins 3-6 weeks after completing induction
Newly diagnosed, low-risk APL
Induction: The typical dose is 0.15 mg/kg of bodyweight, injected into a vein once a day with tretinoin (ATRA) until bone marrow remission or for up to 60 days.
Consolidation: The typical dose is 0.15 mg/kg of bodyweight, injected into a vein once a day with tretinoin (ATRA) for 5 days during weeks 1-4. After that, there is a 4-week break with no medication.
This dosing schedule is repeated for a total of 4 cycles.
You won’t receive any tretinoin (ATRA) during weeks 5-6 of the last cycle.
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are receiving this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Refractory or relapsed acute promyelocytic leukemia (APL) in children and adults who have previously been treated with a retinoid and anthracycline chemotherapy
Newly diagnosed, low-risk acute promyelocytic leukemia (APL) in adults, given together with tretinoin (all-trans retinoic acid (ATRA))
Acute promyelocytic leukemia (APL) with specific gene changes
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