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Flurazepam Side Effects

In Summary

Commonly reported side effects of flurazepam include: drowsiness. Other side effects include: dizziness, vertigo, insomnia, confusion, headache, and irritability. See below for a comprehensive list of adverse effects.

For the Consumer

Applies to flurazepam: oral capsule

In addition to its needed effects, some unwanted effects may be caused by flurazepam. In the event that any of these side effects do occur, they may require medical attention.

Major Side Effects

You should check with your doctor immediately if any of these side effects occur when taking flurazepam:

  • Black, tarry stools
  • blurred vision
  • chest pain
  • chills
  • confusion
  • cough
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • feeling like you will pass out
  • fever
  • large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
  • painful or difficult urination
  • slurred speech
  • sore throat
  • sores, ulcers, or white spots on the lips or in the mouth
  • sweating
  • swollen glands
  • unusual bleeding or bruising
  • unusual tiredness or weakness
Incidence not known:
  • Change in consciousness
  • clumsy movement, moving from side to side
  • confusion about identity, place, and time
  • falling
  • fast, irregular, pounding, or racing heartbeat or pulse
  • loss of consciousness
  • shakiness and unsteady walk
  • unsteadiness, trembling, or other problems with muscle control or coordination
  • unusual drowsiness, dullness, tiredness, weakness or feeling of sluggishness

Minor Side Effects

Some of the side effects that can occur with flurazepam may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

  • Bitter taste
  • blurred vision
  • burning eyes
  • difficulty in focusing
  • discouragement
  • dry mouth
  • false or unusual sense of well-being
  • feeling of warmth
  • feeling sad or empty
  • hallucinations
  • increased watering of the mouth
  • itching skin or skin rash
  • loss of appetite
  • loss of interest or pleasure
  • mood or mental changes
  • nightmares
  • redness of the face, neck, arms and occasionally, upper chest
  • restlessness
  • sweating
  • trouble concentrating
  • trouble sleeping
  • unusual excitement, nervousness, restlessness, or irritability
  • weight loss
Incidence not known:
  • Constipation
  • diarrhea
  • fear
  • headache
  • heartburn
  • joint pain
  • nausea
  • stomach upset
  • talkativeness
  • vomiting

For Healthcare Professionals

Applies to flurazepam: oral capsule

Nervous system

Common (1% to 10%): Reduced alertness, confusion, headache, dizziness, ataxia
Rare (less than 0.1%): Difficulty in focusing, faintness, slurred speech, confusion, restlessness, vertigo
Frequency not reported: CNS-depressant effects, next-day impairment, nervousness, talkativeness, drowsiness, staggering[Ref]


Common (1% to 10%): Numbed emotions
Rare (less than 0.1%): Euphoria, depression, hallucinations
Frequency not reported: Withdrawal syndrome, abnormal thinking, behavior changes, complex behaviors, worsening of depression, apprehension, irritability[Ref]


Common (1% to 10%): Fatigue
Frequency not reported: Weakness[Ref]


Rare (less than 0.1%): Dry mouth, bitter taste, excessive salivation
Frequency not reported: Heartburn, upset stomach, nausea, vomiting, diarrhea, constipation, gastrointestinal pain[Ref]


Rare (less than 0.1%): Elevated SGOT/SGPT, total and direct bilirubin elevations, elevated alkaline phosphatase
Frequency not reported: Jaundice[Ref]


Very rare (less than 0.01%): Severe anaphylactic/anaphylactoid reactions[Ref]


Frequency not reported: Palpitation, chest pain[Ref]


Rare (less than 0.1%): Sweating, pruritus, skin rash[Ref]


The most commonly reported side effects were headache, dizziness, muscle weakness, ataxia, and double vision.[Ref]


Frequency not reported: Genitourinary complaints, changes in libido, urinary retention[Ref]


Rare (less than 0.1%): Leukopenia, granulocytopenia
Frequency not reported: Blood dyscrasias[Ref]


Rare (less than 0.1%): Anorexia[Ref]


Common (1% to 10%): Muscle weakness
Frequency not reported: Body/joint pain[Ref]


Common (1% to 10%): Double vision
Rare (less than 0.1%): Blurred vision, burning eyes
Frequency not reported: Visual disturbance[Ref]


1. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

2. "Product Information. Dalmane (flurazepam)." Roche Laboratories, Nutley, NJ.

Not all side effects for flurazepam may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.