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Dalmane Side Effects

Generic Name: flurazepam

Note: This page contains information about the side effects of flurazepam. Some of the dosage forms included on this document may not apply to the brand name Dalmane.

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

For the Consumer

Applies to flurazepam: oral capsule

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

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 from a lying or sitting position suddenly
  • feeling like you will pass out
  • fever
  • painful or difficult urination
  • shortness of breath
  • 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

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
  • loss of appetite
  • loss of interest or pleasure
  • mood or mental changes
  • nightmares
  • redness of the face, neck, arms and occasionally, upper chest
  • restlessness
  • skin rash
  • 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

Nervous system side effects have been common and most frequently have included drowsiness, dizziness, and sedation. Headache, anterograde amnesia, hyperexcitability, cognitive disturbances, oral-buccal dyskinesia, and ataxia have also been observed.[Ref]

Flurazepam may cause a greater degree of sedation and psychomotor impairment in older patients compared to other benzodiazepines commonly used as hypnotics. The reason for this increased sensitivity may be related to a prolonged elimination half-life of desalkylflurazepam in elderly patients. One study has suggested that elderly patients who experienced a fall in the hospital were more likely to be taking flurazepam than those elderly patients who did not experience a fall.[Ref]


Psychiatric side effects have included confusion, agitation, depression, secondary mania, and hallucinations.[Ref]


Other side effects have included tolerance to the pharmacologic effects of flurazepam (the active ingredient contained in Dalmane) and withdrawal symptoms after either abrupt cessation or fast tapering of flurazepam. Withdrawal symptoms may include agitation, restlessness, anxiety, depression, insomnia, tremor, abdominal discomfort, blurred vision, vomiting, and sweating. Psychosis, delirium, and seizures have been observed during withdrawal from other benzodiazepines.

Daytime sedation and, less frequently, rebound insomnia (a worsening of sleep following cessation of therapy) and other sleep disturbances have been reported.[Ref]


Gastrointestinal side effects have included nausea, vomiting, bad taste, dry mouth, constipation, and diarrhea. Many of these symptoms have occurred at frequencies similar to or less than placebo.[Ref]


Respiratory side effects have included cases of respiratory depression manifested by an increase in the number of obstructive apneas during sleep.[Ref]


Hepatic side effects have included several cases of intrahepatic cholestasis.[Ref]


Hypersensitivity side effects to flurazepam (the active ingredient contained in Dalmane) have rarely been reported.[Ref]

A number of case reports have suggested that flurazepam may cause a drug-induced encephalopathy in patients with end-stage renal disease undergoing hemodialysis. Specific findings reported include altered consciousness, asterixis, abnormal EEG, and in one patient, biochemical evidence of liver disease.[Ref]


Local side effects have included a case of peripheral ischemia following injection of flurazepam (the active ingredient contained in Dalmane) In that case, a known intravenous drug abuser crushed oral flurazepam tablets (and possibly other tablets) and injected them into a finger. Distal necrosis ensued and required amputation of the affected finger.[Ref]


1. Cunningham TA "Letter: Adverse reaction to flurazepam." Can Med Assoc J 112 (1975): 805

2. Kaplan SR, Murkofsky C "Oral-buccal dyskinesia symptoms associated with low-dose benzodiazepine treatment." Am J Psychiatry 135 (1978): 1558-9

3. Juhl RP, Daugherty VM, Kroboth PD "Incidence of next-day anterograde amnesia caused by flurazepam hydrochloride and triazolam." Clin Pharm 3 (1984): 622-5

4. Bixler EO, Kales A, Brubaker BH, Kales JD "Adverse reactions to benzodiazepine hypnotics: spontaneous reporting system." Pharmacology 35 (1987): 286-300

5. Greenblatt DJ, Shader RI, Divoll M, Harmatz JS "Adverse reactions to triazolam, flurazepam, and placebo in controlled clinical trials." J Clin Psychiatry 45 (1984): 192-5

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

7. Mendelson WB, Weingartner H, Greenblatt DJ, Garnett D, Gillin JC "A clinical study of flurazepam." Sleep 5 (1982): 350-60

8. Olajide D, Lader M "Depression following withdrawal from long-term benzodiazepine use: a report of four cases." Psychol Med 14 (1984): 937-40

9. Bond WS, Schwartz M "Withdrawal reactions after long-term treatment with flurazepam." Clin Pharm 3 (1984): 316-8

10. Berlin RM, Conell LJ "Withdrawal symptoms after long-term treatment with therapeutic doses of flurazepam: a case report." Am J Psychiatry 140 (1983): 488-90

11. Fang MH, Ginsberg AL, Dobbins WO, 3d "Cholestatic jaundice associated with flurazepam hydrochloride." Ann Intern Med 89 (1978): 363-4

12. Reynolds R, Lloyd DA, Slinger RP "Cholestatic jaundice induced by flurazepam hydrochloride." Can Med Assoc J 124 (1981): 893-4

13. Rapp MS "Reaction to flurazepam." Can Med Assoc J 105 (1971): 1020-1

14. Reynolds IS "Digital loss resulting from drug abuse." Br J Clin Pract 34 (1980): 246,

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