Methadone HCL Syringe Side Effects by Likelihood and Severity

COMMON side effects


If experienced, these tend to have a Severe expression

  • Low Blood Pressure

If experienced, these tend to have a Less Severe expression

  • Constipation
  • Dizziness
  • Drowsiness
  • Fainting
  • Generalized Weakness
  • Nausea
  • Vomiting

INFREQUENT side effects


If experienced, these tend to have a Severe expression

  • Confusion
  • Decreased Lung Function
  • Fast Heartbeat
  • Slow Heartbeat
  • Trouble Breathing

If experienced, these tend to have a Less Severe expression

  • A Change In Vision
  • A Spasm Of The Ureter
  • Decreased Appetite
  • Decreased Urine Production
  • Difficulty Sleeping
  • Dry Mouth
  • Excessive Sweating
  • False Sense Of Well-Being
  • Head Pain
  • Nervousness
  • Orthostatic Hypotension, A Form Of Low Blood Pressure
  • Spasm Of A Bile Duct Tract
  • Stomach Cramps

RARE side effects


If experienced, these tend to have a Severe expression

  • A Condition Where The Body Is Unable To Maintain Adequate Blood Flow Called Shock
  • A Condition With Muscle Tissue Breakdown Called Rhabdomyolysis
  • A High Prolactin Level
  • A Significant Type Of Allergic Reaction Called Anaphylaxis
  • A Skin Rash
  • Abnormal Heart Rhythm
  • Complete Stoppage Of The Heart
  • Decreased Function Of The Adrenal Gland
  • Deficiency Of A Substance That Promotes Masculinization
  • Fluid In The Lungs
  • Hallucinations
  • Heart Failure
  • Hives
  • Increased Spinal Fluid Pressure
  • Itching
  • Low Amount Of Magnesium In The Blood
  • Low Amount Of Potassium In The Blood
  • Lung Failure Causing Loss Of Breath
  • Prolonged QT Interval On EKG
  • Seizures
  • Serotonin Syndrome, A Type Of Disorder With High Serotonin Levels
  • Torsades De Pointes, A Type Of Abnormal Heart Rhythm
  • Ventricular Fibrillation, A Heart Rhythm Disorder

If experienced, these tend to have a Less Severe expression

  • A Delay When Starting To Urinate
  • A Painful, Red Or Swollen Tongue
  • Abnormal Function And Activity Of The Testis
  • Absence Of Menstrual Periods
  • Agitation
  • Altered Interest In Having Sexual Intercourse
  • An Inability To Completely Empty The Bladder
  • Decreased Sperm Motility
  • Heart Throbbing Or Pounding
  • Infertility
  • Inflammation Of The Vein, Or Phlebitis After Infusion
  • Low Sperm Count
  • Temporary Redness Of Face And Neck
  • The Inability To Have An Erection
  • Visible Water Retention
  • Weight Gain

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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.