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Seconal Side Effects

Generic Name: secobarbital

Note: This document contains side effect information about secobarbital. Some of the dosage forms listed on this page may not apply to the brand name Seconal.

For the Consumer

Applies to secobarbital: oral capsule

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Signs of low mood (depression), thoughts of killing yourself, nervousness, emotional ups and downs, thinking that is not normal, anxiety, or lack of interest in life.
  • Signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
  • Shortness of breath.
  • Change in balance.
  • Change in how you act.
  • Feeling confused.
  • Bad dreams.
  • Feeling nervous and excitable.
  • Hallucinations (seeing or hearing things that are not there).
  • Not able to sleep.
  • Feeling very tired or weak.
  • Very bad dizziness or passing out.
  • Slow heartbeat.
  • Memory problems or loss.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Feeling sleepy.
  • Feeling sleepy the next day.
  • Dizziness.
  • Headache.
  • Feeling tired or weak.
  • Dry mouth.
  • Upset stomach.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.

For Healthcare Professionals

Applies to secobarbital: injectable solution, oral capsule

Nervous system

Nervous system side effects have included somnolence, headache, confusion, hyperkinesias, ataxia, and dizziness.[Ref]

Cardiovascular

Cardiovascular side effects have included bradycardia, hypotension, and syncope.[Ref]

Gastrointestinal

Gastrointestinal side effects have included nausea, vomiting, and constipation.[Ref]

Hypersensitivity

Hypersensitivity reactions have included angioedema, skin rash, and exfoliative dermatitis.[Ref]

Oncologic

Oncologic side effects have included a possible increased frequency of malignancy (particularly liver cancer and brain tumors) following use of phenobarbital and other barbiturates.[Ref]

Other

Other side effects have included physical and psychological dependence. Withdrawal symptoms have been reported when secobarbital (the active ingredient contained in Seconal) therapy has been discontinued suddenly.[Ref]

Psychiatric

Psychiatric side effects have included agitation, nightmares, nervousness, psychiatric disturbance, hallucinations, insomnia, anxiety, and abnormal thinking.[Ref]

Respiratory

Respiratory side effects have included hypoventilation and apnea.[Ref]

References

1. "Product Information. Seconal Sodium (secobarbital)." Marathon Pharmaceuticals, Deerfield, IL.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

More about Seconal (secobarbital)

Consumer resources

Other brands: Seconal Sodium

Professional resources

Related treatment guides

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