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    Side Effects

    List Phenytoin side effects by likelihood and severity.

    The following side effects are associated with phenytoin:

    Common side effects of phenytoin:

    • ConfusedSevere
    • Fever Caused By Administration Of A DrugSevere
    • Involuntary Eye MovementSevere
    • NervousSevere
    • Over ExcitementSevere
    • Overgrowth Of Gums Onto TeethSevere
    • RashSevere
    • Slurred SpeechSevere
    • Toxic Effect On Brain Or Spinal Cord FunctionSevere
    • UncoordinatedSevere
    • ConstipationLess Severe
    • DizzyLess Severe
    • DrowsinessLess Severe
    • Nausea And VomitingLess Severe

    Infrequent side effects of phenytoin:

    • Easily Angered Or AnnoyedSevere
    • Peripheral NeuropathySevere
    • Abnormal Forward Position Of One Or Both JawsLess Severe
    • Chronic Trouble SleepingLess Severe
    • Discolored Spots And Small Elevations Of The SkinLess Severe
    • Enlarged BreastsLess Severe
    • Enlargement Of The LipsLess Severe
    • Excessive HairinessLess Severe
    • Head PainLess Severe
    • Numbness And TinglingLess Severe
    • Taste ProblemsLess Severe
    • TwitchingLess Severe

    Rare side effects of phenytoin:

    • A Disorder Of The Body's Use Of CalciumSevere
    • Acquired Decrease Of All Cells In The BloodSevere
    • Acute Liver FailureSevere
    • Blood DisorderSevere
    • Broken BoneSevere
    • Cerebellar AtrophySevere
    • Decreased Blood PlateletsSevere
    • Decreased White Blood CellsSevere
    • Deficiency Of Granulocytes A Type Of White Blood CellSevere
    • DRESS SyndromeSevere
    • DyskinesiaSevere
    • Having Thoughts Of SuicideSevere
    • HepatitisSevere
    • Hypersensitivity Drug ReactionSevere
    • Increase Or Decrease In Vitamin DSevere
    • Increased Eosinophils In The BloodSevere
    • Involuntary QuiveringSevere
    • Muscle Problems That Cause Abnormal MovementSevere
    • Paroxysmal ChoreoathetosisSevere
    • Periarteritis NodosaSevere
    • Peyronie's DiseaseSevere
    • Skin Rash With SloughingSevere
    • Stevens-Johnson SyndromeSevere
    • Swollen Lymph NodesSevere
    • Systemic Lupus ErythematosusSevere
    • Toxic Epidermal NecrolysisSevere
    • X-Ray Results Showing Lung Tissue ChangesSevere
    • Yellowing Of Skin Or Eyes From Bile Flow ProblemsSevere
    • Coarsening Of Facial FeaturesLess Severe
    • Decreased Calcification Or Density Of BoneLess Severe
    • High Blood SugarLess Severe
    • Problem BehaviorLess 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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