Singulair Side Effects
What should I watch for?
Visit your doctor or health care professional for regular checks on your progress. Tell your doctor or health care professional if your allergy or asthma symptoms do not improve. Take your medicine even when you do not have symptoms. Do not stop taking any of your medicine(s) unless your doctor tells you to.
Patients and their families should watch for new or worsening thoughts of suicide or depression. Also watch for sudden changes in feelings such as feeling anxious, agitated, panicky, irritable, hostile, aggressive, impulsive, severely restless, overly excited and hyperactive, or not being able to sleep. Any worsening of mood or thoughts of suicide or dying should be reported to your health care professional right away.
Common and Rare Side Effects
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:
Abdominal or stomach pain
general feeling of discomfort or illness
pain or tenderness around the eyes and cheekbones
shortness of breath or troubled breathing
tightness of the chest
trouble with swallowing
unusual tiredness or weakness
Pus in the urine
Incidence not known
attempts at killing oneself
confusion about identity, place, and time
fast, irregular, pounding, or racing heartbeat or pulse
feeling sad or empty
hives or welts
itching, puffiness, or swelling of the eyelids or around the eyes, face, lips, or tongue
lack of appetite
pains in the stomach, side, or abdomen, possibly moving to the back
redness of the skin
shaking or trembling of the hands or feet
trouble with concentrating
unable to sleep
unpleasant breath odor
upper right abdominal or stomach pain
vomiting of blood
yellow eyes 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:
Acid or sour stomach
change in near or distance vision
lack or loss of strength
skin rash, encrusted, scaly and oozing
stomach discomfort, upset, or pain
Incidence not known
Burning, crawling, itching, numbness, prickling, “pins and needles”, or tingling feelings
dreams that are unusual
increased tendency to bleed
large, flat, blue or purplish patches on the skin
muscle aching or cramping
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.