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Side Effects

List guanfacine side effects by likelihood and severity.

The following side effects are associated with guanfacine:

Common side effects of guanfacine:

  • DrowsinessLess Severe
  • Dry MouthLess Severe
  • Inducing of a Relaxed Easy StateLess Severe
  • Low EnergyLess Severe
  • Weight GainLess Severe

Infrequent side effects of guanfacine:

  • ConfusedSevere
  • Abnormally Low Blood PressureLess Severe
  • Altered Interest in Having Sexual IntercourseLess Severe
  • Chronic Trouble SleepingLess Severe
  • DizzyLess Severe
  • Easily Angered or AnnoyedLess Severe
  • Feel Like Throwing UpLess Severe
  • Feeling WeakLess Severe
  • Frequent UrinationLess Severe
  • Head PainLess Severe
  • Heart Throbbing or PoundingLess Severe
  • Inability to have an ErectionLess Severe
  • Incomplete or Infrequent Bowel MovementsLess Severe
  • IndigestionLess Severe
  • Loss of AppetiteLess Severe
  • NightmaresLess Severe
  • Problems with Bladder ControlLess Severe
  • SluggishnessLess Severe
  • Throwing UpLess Severe

Rare side effects of guanfacine:

  • Abnormal Functioning of the Sinus Node of the HeartSevere
  • Allergic Reaction caused by a DrugSevere
  • Atrioventricular Heart BlockSevere
  • Chest PainSevere
  • Fast HeartbeatSevere
  • Having Thoughts of SuicideSevere
  • SeizuresSevere
  • Skin Rash with SloughingSevere
  • AnxiousLess Severe
  • Blurred VisionLess Severe
  • DepressionLess Severe
  • Feeling FaintLess Severe
  • Hair LossLess Severe
  • HallucinationLess Severe
  • Intense Abdominal PainLess Severe
  • Involuntary QuiveringLess Severe
  • ItchingLess Severe
  • Joint PainLess Severe
  • Leg CrampsLess Severe
  • Loss of Skin ColorLess Severe
  • Not Feeling WellLess Severe
  • Numbness and TinglingLess Severe
  • Pink EyeLess Severe
  • RashLess Severe
  • Sensation of Spinning or WhirlingLess Severe
  • Skin InflammationLess Severe
  • Slow HeartbeatLess Severe
  • Taste ProblemsLess Severe
  • Trouble BreathingLess 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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