Klonopin Side Effects

Generic name: clonazepam

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

Some side effects of Klonopin may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

For the Consumer

Applies to clonazepam: oral tablet, oral tablet disintegrating

Get emergency medical help if you have any of these signs of an allergic reaction while taking clonazepam (the active ingredient contained in Klonopin) hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, depression, anxiety, or if you feel agitated, irritable, hostile, aggressive, restless, hyperactive (mentally or physically), or have thoughts about suicide or hurting yourself.

Call your doctor at once if you have a serious side effect such as:

• confusion, hallucinations, unusual thoughts or behavior;

• weak or shallow breathing;

• unusual risk-taking behavior, no fear of danger;

• unusual or involuntary eye movements;

• pounding heartbeats or fluttering in your chest;

• painful or difficult urination, urinating less than usual;

• pale skin, easy bruising or bleeding; or

• new or worsening seizures.

Less serious side effects of clonazepam may include:

• drowsiness, dizziness, problems with thinking or memory;

• tired feeling, muscle weakness, loss of balance or coordination;

• slurred speech, drooling or dry mouth, sore gums;

• runny or stuffy nose;

• loss of appetite, nausea, diarrhea, constipation;

• blurred vision;

• headache;

• sleep problems (insomnia);

• skin rash; or

• weight changes.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.

For Healthcare Professionals

Applies to clonazepam: oral tablet, oral tablet disintegrating

Nervous system

Nervous system side effects are common, particularly at the initiation of therapy and include drowsiness, fatigue, ataxia, confusion, depression, daytime anxiety, and amnesia. Nystagmus, diplopia, vertigo, headache, respiratory depression, tremor and slurred speech have also been reported less frequently.

Sedation may initially occur in up to 50% of treated patients. Ataxia may occur in 30% of patients. Five to 6% of patients treated with clonazepam for seizures may develop more frequent seizures or a new type of seizure disorder. Weakness and hypotonia have also been reported. A case report has suggested that clonazepam may induce Tourette's syndrome.

Psychiatric

Behavioral problems have been reported in as many as 30% of treated patients.

Psychiatric side effects have been reported and include behavioral disinhibition (particularly sexual disinhibition), depression, and rarely, psychosis and mania.

Other

Other side effects have included withdrawal symptoms (similar to those which may occur after withdrawal of barbiturates and alcohol) which have been reported after abrupt cessation of clonazepam (the active ingredient contained in Klonopin) Specifically, seizures, agitation, restlessness, anxiety, delirium, psychosis, dysphoria, insomnia, tremor, abdominal cramps, vomiting, rash, and sweating have been reported to have occurred, especially after long-term therapy.

Genitourinary

In one study, anorgasmia occurred in 44% of patients treated with clonazepam (the active ingredient contained in Klonopin) while anorgasmia occurred in only 6% of patients treated with placebo.

Genitourinary side effects may include urinary incontinence, anorgasmia, ejaculatory delay, and erectile dysfunction.

Hematologic

Hematologic side effects including thrombocytopenia have been reported rarely.

Gastrointestinal

Gastrointestinal side effects including hypersalivation, diarrhea, constipation, nausea, increased appetite, and anorexia have been reported.

Respiratory

Respiratory side effects including bronchial hypersecretion have been reported.

Dermatologic

Dermatologic side effects have included cases of rashes associated with clonazepam (the active ingredient contained in Klonopin) therapy. A case of erythema multiforme associated with clonazepam therapy has also been reported.

Ocular

Clonazepam (the active ingredient contained in Klonopin) is contraindicated in patients with narrow angle glaucoma.

Ocular side effects including acute worsening of narrow angle glaucoma is possible with clonazepam therapy.

Metabolic

Metabolic side effects have included exacerbation of seizure disorders in some patients with acute intermittent porphyria. However, a case report has suggested that clonazepam (the active ingredient contained in Klonopin) may be beneficial in this setting as well.

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 information does not endorse drugs, diagnose patients, or recommend therapy. This drug 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 drug combination in no way should be construed to indicate that the drug of drug combination is safe, effective, or appropriate for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of information 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 drugs you are taking, check with your doctor, nurse, or pharmacist.