Mesalamine is used to help with an inflammatory bowel disease called ulcerative colitis (UC). It helps relieve symptoms of mild or moderate UC, such as stomach pain, diarrhea, and gut inflammation. This medication can also be used to maintain remission (prevent UC flare-ups) in adults. There are many brand names for mesalamine on the market, and they all have lower-cost generics available. The dosage depends on the brand and formulation of mesalamine you have. In general, this medication can cause side effects like headache and indigestion.
Ulcerative colitis (UC)
Mesalamine is an aminosalicylate. It's unclear how mesalamine exactly works. But it appears to work inside the bowels (gut) to lower gut inflammation, which helps relieve symptoms of UC.
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 immediately if any of the following side effects occur:
Less common
Bloody stools
bloody urine
blurred vision
chest tightness
chills
clay-colored stools
dark urine
difficulty with breathing
dizziness
full or bloated feeling
general feeling of discomfort or illness
headache
itching, skin rash
joint pain
loss of appetite
muscle aches and pains
nervousness
pain or tenderness around the eyes and cheekbones
pounding in the ears
pressure in the stomach
runny or stuffy nose
shivering
slow or fast heartbeat
stomach cramps
sweating
swelling of the stomach area
trouble sleeping
unpleasant breath odor
unusual tiredness or weakness
vomiting
vomiting of blood
yellow eyes or skin
Incidence not known
Black, tarry stools
blistering, peeling, or loosening of the skin
change in the ability to see colors, especially blue or yellow
chest discomfort
decreased frequency or amount of urine
greatly increased frequency of urination or amount of urine
hives or welts
hoarseness
inability to move the arms and legs
increased thirst
indigestion
large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or genitals
light-colored stools
lower back or side pain
muscle weakness, sudden and progressing
pain in the ankles or knees
painful or difficult urination
painful, red lumps under the skin, mostly on the legs
rapid breathing
red skin lesions, often with a purple center
red, irritated eyes
severe nausea or vomiting
sores, ulcers, or white spots in the mouth or on the lips
stomach tenderness
sudden numbness and weakness in the arms and legs
swelling of the feet or lower legs
swollen or painful glands
thickening of bronchial secretions
unusual bleeding or bruising
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
Less common
belching
continuing ringing or buzzing or other unexplained noise in the ears
difficulty with moving
dizziness or lightheadedness
excess air or gas in the stomach or bowels
feeling of constant movement of self or surroundings
hair loss or thinning of the hair
hearing loss
muscle stiffness
passing gas
sensation of spinning
stomach discomfort or upset
Incidence not known
Burning, numbness, tingling, or painful sensations
unsteadiness or awkwardness
weakness in the arms, hands, legs, or feet
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.
Easy to take since it's a pill that's swallowed
Generally mild side effects
A first-choice option for preventing flare-ups in adults with mild UC
Lower-cost generics available
Typically need to take a few pills for each dose
Can take a few weeks before you start to feel the effects
Might cause kidney stones and make your skin more sensitive to the sun
Might not be the best option for people with liver problems
Tips for all generics and brands of mesalamine:
Swallow the tablets or capsules whole. Don't cut, crush, break, or chew them. If you have trouble swallowing, ask your healthcare provider for specific recommendations for the oral mesalamine form you have (or refer to the tips for each form below).
Drink plenty of fluids while you're taking mesalamine to prevent kidney stones. Contact your provider if you experience any signs or symptoms of a kidney stone (e.g., severe side or back pain, blood in urine).
Your skin can become more sensitive to sunlight and you might get sunburns more easily while you're taking mesalamine. Make sure to avoid direct sun exposure, wear protective clothing, and apply sunscreen when you're outside.
If you're switching between different oral mesalamine products, stop taking your previous mesalamine medications and take your new mesalamine prescription as instructed by your provider. Different forms of oral mesalamine have different instructions.
Don't substitute different mesalamine products with one another without first checking with your provider. Many formulations aren't the same. For example, one 800 mg mesalamine delayed-release tablet can't be substituted with two 400 mg mesalamine delayed-release capsules.
Tips for Apriso and its generic extended-release capsule:
Take the medication with or without food.
Avoid taking this medication with any antacids to make sure that you get the full benefit of your dose. Antacids can affect how well mesalamine gets absorbed into your body.
Tips for Asacol HD and its generic delayed-release tablet:
Take the medication on an empty stomach, at least 1 hour before and 2 hours after a meal.
You might see parts of the tablet in your stool. Talk to your provider if this happens a lot.
Always close the bottle tightly to protect the tablets from moisture. Keep the medication at room temperature in a dry place.
Tips for Delzicol and its generic delayed-release capsule:
Take the medication with or without food.
If you're having trouble swallowing the capsules, you can open the capsules and swallow the small tablets that are inside individually (each capsule contains four 100 mg tablets). Make sure to swallow the tablets whole; don't cut, break, crush, or chew them.
You might see parts of the tablets in your stool. Talk to your provider if you notice that this happens a lot.
Keep the container closed tightly to protect the capsules from any moisture. Don't take the drying pouches out of the bottle.
Tips for Pentasa brand and its generic extended-release capsule:
Take the medication with or without food.
If you have trouble swallowing the capsules, you can open them and sprinkle the beads that are inside onto applesauce or yogurt. Once the beads are sprinkled on top, eat the applesauce or yogurt right away. Don't crush or chew the beads.
Mesalamine 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.
Risk factors: Current or history of kidney problems | Taking medications that can harm the kidneys
Some people taking mesalamine developed kidney problems during treatment. These problems can include kidney stones, kidney damage, and sometimes even kidney failure. Your risk for kidney damage is higher if you have a history of kidney problems or if you're taking other medications that can harm the kidneys, such as nonsteroidal anti‑inflammatory drugs (NSAIDs) like ibuprofen (Advil, Motrin). Let your healthcare provider know about your medical history and all the medications you take or plan to take.
Your provider will check your kidney function through blood work before you start mesalamine and periodically throughout treatment. Make sure to drink enough fluids each day to prevent kidney stones. Contact your provider if you have trouble urinating, notice a change in how much you urinate, have blood in the urine, or feel back or side pain. These can be signs of kidney problems.
Some people can have an abnormal reaction to mesalamine called acute intolerance syndrome. This reaction can be hard to tell apart from a flare-up of UC. Symptoms include stomach cramping or pain, bloody diarrhea, and sometimes fever, headache, and rash. Let your healthcare provider know if you notice these symptoms. You might need to stop treatment with mesalamine to help these symptoms go away.
Risk factors: Current or history of liver problems
While uncommon, some people taking mesalamine developed liver problems during treatment. In addition, some people who already had liver problems later had liver failure after they started taking mesalamine. Let your healthcare provider know if you have liver problems before starting this medication so they can discuss the risks and benefits with you. Contact your provider right away if you notice signs of liver problems, like yellowing of the skin or eyes, dark urine, tiredness, or right-sided stomach pain, during treatment with mesalamine.
Risk factors: Previous allergic reaction to sulfasalazine (Azulfidine)
Though rare, it's possible to have an allergic reaction to mesalamine. These reactions can be serious and sometimes life-threatening. Allergic reactions can make it difficult to breathe, cause a severe rash, or even affect some of your organs (e.g., heart, liver, kidneys). Get medical help right away if you have any symptoms of an allergic reaction, such as itchiness; hives; shortness of breath; chest tightness; and swelling of your lips, tongue, face, or eyes.
Mesalamine can also possibly cause severe skin reactions to happen. Stop taking mesalamine and seek emergency medical help as soon as possible if you experience rash, discolored patches of skin, skin peeling, blisters, or painful mouth sores. Sometimes, these skin reactions can happen along with fever and body aches.
Some tablet and capsule forms of mesalamine have coatings that contain iron oxide for coloring. Tell your healthcare provider if you take or plan to take any iron supplementation (by mouth or by infusion through the vein) or if you have medical conditions that raise your risk for too much iron in your body. To avoid the harmful effects of taking too much iron, your provider should discuss with you about being aware of all your sources of iron.
The Apriso extended-release capsules contain phenylalanine. This ingredient can be harmful for people with a genetic condition called phenylketonuria (PKU). Talk to your healthcare provider if you have PKU so they can prescribe a different version of mesalamine that's safer for you.
Each oral form and brand of mesalamine has specific dosing instructions. Make sure to read your dosing instructions carefully, and refer to the Pharmacist tips for more information about how to take the mesalamine form you have.
Treatment of mild or moderate UC
Asacol HD and its generics (delayed-release tablet):
Adults: The typical dose is 1,600 mg (two 800 mg tablets) by mouth three times a day for 6 weeks.
Delzicol and its generics (delayed-release capsule):
Adults: The typical dose is 800 mg (two 400 mg capsules) by mouth three times a day. You'll typically take the medication for 6 weeks.
Children 5 years or older weighing 37 lbs to 198 lbs: The provider will determine the dose based on your child's body weight. The medication is taken by mouth twice a day for 6 weeks. The maximum daily dosage ranges from 1.2 to 2.4 grams per day.
Pentasa and its generics (extended-release capsule):
Adults: The typical dose is 1 gram (four 250 mg capsules or two 500 mg capsules) by mouth four times a day. You'll typically take the medication for up to 8 weeks.
Maintenance of remission of UC
Apriso and its generics (extended-release capsule):
Adults: The typical dose is 1.5 grams (four 0.375 gram capsules) by mouth once a day in the morning.
Delzicol and its generics (delayed-release capsule):
Adults: The typical dose is 1,600 mg (four 400 mg capsules) by mouth per day. The total daily dose is separated into 2 to 4 doses during the day.
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.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Allergy to aspirin or other salicylates
Mild-to-moderate ulcerative colitis (UC) in people age 5 years and older
Ulcerative colitis (UC) - immediate-release and delayed release tablets
Rheumatoid arthritis (RA) - delayed-release tablets only
Polyarticular juvenile rheumatoid arthritis - delayed-release tablets only
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