VENLAFAXINE HCL ER Side Effects by Likelihood and Severity

COMMON side effects

If experienced, these tend to have a Severe expression i

  • disturbance in the ability of the eye to focus
  • headache

If experienced, these tend to have a Less Severe expression i

  • problems with ejaculation
  • dry mouth
  • constipation
  • the inability to have an erection
  • drowsiness
  • dizziness
  • difficulty sleeping
  • excessive sweating
  • muscle tremors
  • taste impairment
  • decreased appetite
  • nausea
  • vomiting
  • nervousness
  • a feeling of pins and needles on skin
  • generalized weakness
  • anxious feelings

INFREQUENT side effects

If experienced, these tend to have a Severe expression i

  • high cholesterol
  • abnormal sexual function
  • high blood pressure
  • itching
  • a feeling of restlessness with inability to sit still
  • chest pain
  • an inability to completely empty the bladder
  • an increased need to urinate often
  • fast heartbeat

If experienced, these tend to have a Less Severe expression i

  • altered interest in having sexual intercourse
  • feelings of hostility
  • a migraine headache
  • bronchitis
  • indigestion
  • inflammation or infection of the vagina
  • neck pain
  • sensation of spinning or whirling
  • chills
  • muscle twitching
  • visible water retention
  • weight gain
  • weight loss
  • yawning
  • gas
  • diarrhea
  • irritability
  • orgasm problems
  • abnormal dreams

RARE side effects

If experienced, these tend to have a Severe expression i

  • low blood sugar
  • a disorder with excess antidiuretic hormone called syndrome of inappropriate antidiuretic hormone
  • low amount of sodium in the blood
  • low blood counts due to bone marrow failure
  • decreased blood platelets
  • very low levels of granulocytes, a type of white blood cell
  • manic behavior
  • mood changes
  • suicidal thoughts
  • tardive dyskinesia, a disorder characterized by involuntary movements of the face, mouth and tongue
  • extrapyramidal disease, a type of movement disorder
  • neuroleptic malignant syndrome, a reaction characterized by fever, muscle rigidity and confusion
  • serotonin syndrome, a type of disorder with high serotonin levels
  • increased pressure in the eye
  • abnormal heart electrical signals
  • torsades de pointes, a type of abnormal heart rhythm
  • ventricular fibrillation, a heart rhythm disorder
  • prolonged QT interval on EKG
  • orthostatic hypotension, a form of low blood pressure
  • bleeding
  • a type of inflammation of the lung called interstitial pneumonitis
  • pneumonia with high amount of eosinophil white blood cells
  • inflammation of the liver called hepatitis
  • bleeding of the stomach or intestines
  • erythema multiforme, a type of allergic skin reaction
  • a skin disorder with blistering and peeling skin called toxic epidermal necrolysis
  • a skin disorder with blistering and peeling skin called Stevens-Johnson syndrome
  • a condition with muscle tissue breakdown called rhabdomyolysis
  • mental status changes
  • seizures
  • fluid retention in the legs, feet, arms or hands
  • trouble breathing
  • difficult or painful urination
  • a significant type of allergic reaction called anaphylaxis
  • a type of allergic reaction called angioedema
  • secondary angle-closure glaucoma, a type of eye disorder
  • pancreatitis
  • abnormal muscle movements
  • takotsubo cardiomyopathy

If experienced, these tend to have a Less Severe expression i

  • a high prolactin level
  • grinding of the teeth
  • dilated pupils
  • abnormally acute hearing or painful sensitivity to sound
  • widening of blood vessels
  • a stuffy and runny nose
  • inflammation of the tissue lining the sinuses
  • pain with menstruation
  • abnormally long or heavy periods
  • bleeding not related to menstrual period
  • increased sensitivity of the skin to the sun
  • hair loss
  • an abnormal increase in muscle tone
  • muscle stiffness
  • delirium
  • flu-like symptoms
  • loss of muscle coordination
  • temporary redness of face and neck
  • nosebleed
  • burping
  • elevation of proteins in the urine
  • abnormal liver function tests
  • intense abdominal pain
  • bulging of the eyes

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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, except 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.