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Side Effects

List Singulair side effects by likelihood and severity.

The following side effects are associated with Singulair:

Common side effects of Singulair:

  • Abnormal Liver Function TestsSevere
  • Acute Infection of the Nose, Throat or SinusLess Severe
  • CoughLess Severe
  • FeverLess Severe
  • Head PainLess Severe
  • Throat IrritationLess Severe

Infrequent side effects of Singulair:

  • BronchitisSevere
  • NearsightednessSevere
  • Skin InfectionSevere
  • The FluSevere
  • DiarrheaLess Severe
  • DizzyLess Severe
  • Feeling WeakLess Severe
  • Infection of the Stomach and IntestinesLess Severe
  • Inflammation of the NoseLess Severe
  • Low EnergyLess Severe
  • Middle Ear InfectionLess Severe
  • RashLess Severe
  • Sinus Irritation and CongestionLess Severe
  • Stomach CrampsLess Severe
  • Stuffy NoseLess Severe
  • ToothacheLess Severe

Rare side effects of Singulair:

  • Allergic Reaction caused by a DrugSevere
  • Allergic Reaction causing Inflammation of Blood VesselsSevere
  • ChickenpoxSevere
  • Decreased Blood PlateletsSevere
  • Erythema MultiformeSevere
  • Feeling Anger Toward SomethingSevere
  • Giant HivesSevere
  • Having Thoughts of SuicideSevere
  • HivesSevere
  • Increased Eosinophils in the BloodSevere
  • Inflammation of the Liver with Stoppage of Bile FlowSevere
  • NosebleedSevere
  • PancreatitisSevere
  • Pink EyeSevere
  • PneumoniaSevere
  • Pneumonia with High Amount of Eosinophil White Blood CellsSevere
  • SeizuresSevere
  • Skin Condition Marked by Red and Painful NodulesSevere
  • Stevens-Johnson SyndromeSevere
  • SuicidalSevere
  • Toxic Epidermal NecrolysisSevere
  • White Blood Cells in Urine in Response to InfectionSevere
  • Abnormal DreamsLess Severe
  • Aggressive BehaviorLess Severe
  • AnxiousLess Severe
  • BruiseLess Severe
  • Chronic Trouble SleepingLess Severe
  • ConfusedLess Severe
  • CrampsLess Severe
  • DepressionLess Severe
  • Disturbance of AttentionLess Severe
  • DrowsinessLess Severe
  • Easily Angered or AnnoyedLess Severe
  • EczemaLess Severe
  • Feel Like Throwing UpLess Severe
  • Feeling RestlessLess Severe
  • HallucinationLess Severe
  • Heart Throbbing or PoundingLess Severe
  • IndigestionLess Severe
  • Infection caused by a VirusLess Severe
  • Inflammation of Skin caused by an AllergyLess Severe
  • Inflammation of the Voice BoxLess Severe
  • Involuntary QuiveringLess Severe
  • ItchingLess Severe
  • Joint PainLess Severe
  • Loss of MemoryLess Severe
  • Muscle PainLess Severe
  • NervousLess Severe
  • NumbnessLess Severe
  • Numbness and TinglingLess Severe
  • SleepwalkingLess Severe
  • Throwing UpLess Severe
  • Visible Water RetentionLess Severe

Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, expect as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.

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