Commonly reported side effects of carbamazepine include: ataxia, dizziness, drowsiness, nausea, and vomiting. Other side effects include: pruritus, speech disturbance, amblyopia, and xerostomia. See below for a comprehensive list of adverse effects.
Applies to carbamazepine: oral capsule extended release, oral suspension, oral tablet, oral tablet chewable, oral tablet extended release
Oral route (Tablet; Tablet, Chewable; Suspension; Tablet, Extended Release; Capsule, Extended Release)
Serious and sometimes fatal dermatologic reactions (including Stevens-Johnson syndrome and toxic epidermal necrolysis) have been reported, especially in patients with the inherited allelic variant HLA-B*1502. Screen genetically at-risk patients prior to receiving carbamazepine. Do not start carbamazepine in patients who test positive for the allele unless the benefit clearly outweighs the risk. Discontinue if you suspect that the patient has a serious dermatologic reaction. Aplastic anemia and agranulocytosis have also been reported. Obtain pretreatment hematological testing and periodically monitor CBC. Consider drug discontinuation if significant bone marrow depression develops.
Along with its needed effects, carbamazepine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur while taking carbamazepine:
Incidence not known
Some side effects of carbamazepine may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Incidence not known
Applies to carbamazepine: compounding powder, intravenous solution, oral capsule extended release, oral suspension, oral tablet, oral tablet chewable, oral tablet extended release
Very common (10% or more): Nausea (29%), vomiting (18%), constipation (10%)
Very rare (less than 0.01%): Colitis, glossitis, stomatitis, pancreatitis
Frequency not reported: Dryness of the mouth, with suppositories occasional rectal irritation may occur, diarrhea, oral ulceration
Postmarketing reports: Gastric distress, abdominal pain, anorexia
Very rare (less than 0.01%): Increase in prolactin (with or without symptoms such as gynecomastia or galactorrhea), impaired male fertility and/or abnormal spermatogenesis, abnormal thyroid function tests (e.g., decreased L-thyroxine [FT4, T4, T3] and increased TSH)
Frequency not reported: Lower serum testosterone, lower free androgen indexes, increased cerebrospinal fluid thyrotropin-releasing hormone levels
Carbamazepine increases the rate of T4 and T3 metabolism and may lead to hypothyroidism in patients with hypothyroidism who are being treated with T4. Carbamazepine may also cause a 20% to 40% decrease in serum total and free T4 concentrations and a smaller decrease in serum total and free T3 concentrations in patients who have no thyroid disease.
Very common (10% or more): Leucopenia
Common (1% to 10%): Eosinophilia, thrombocytopenia, neutropenia
Rare (0.01% to 0.1%): Leukocytosis, lymphadenopathy, folic acid deficiency
Very rare (less than 0.01%): Agranulocytosis, aplastic anemia, pure red cell aplasia, megaloblastic anemia, acute intermittent porphyria, reticulocytosis, hemolytic anemia
Frequency not reported: Aplastic anemia, pancytopenia, bone marrow depression, leukopenia, thrombophlebitis, thromboembolism, adenopathy
Thrombocytopenia is the most common hematologic effect of carbamazepine and may be either mild and transient or severe. Significant decreases in white blood cell counts may occur although the values may still be within the normal range. Often counts will return to baseline during continued therapy, and therefore, discontinuation of carbamazepine may not be necessary. Dose reductions may also result in normalization of white blood cell counts. Aplastic anemia has been reported (although many of the reported cases had confounding exposures to other medications). The manufacturer reports an incidence of 2 per 1,000,000 patients for aplastic anemia and 6 per 1,000,000 patients for agranulocytosis. Cases of reticulocytosis have been reported rarely in association with carbamazepine therapy as well. In addition, cases of hemolytic anemia and erythroid arrest have been reported.
Both humoral and nonimmune mechanisms have been implicated in the etiology of carbamazepine-induced bone marrow suppression.
Rare (0.01% to 0.1%): Disturbances of cardiac conduction
Very rare (less than 0.01%): Bradycardia, arrhythmias, AV-block with syncope, collapse, congestive heart failure, hypertension or hypotension, aggravation of coronary artery disease, thrombophlebitis, thromboembolism
Frequency not reported: Edema
Most of the cases of cardiovascular effects reported have occurred in patients receiving carbamazepine for trigeminal neuralgia. The reported effects included congestive heart failure, edema, hypotension, syncope and arrhythmias. In general, the doses were titrated quickly because of severe pain. Many of the doses were higher than those used to treat epilepsy. Many of the reported cardiovascular effects resolved after discontinuation of carbamazepine.
Rigidity and oculogyric crises have been reported. Impairment of psychomotor function has been noted in association with use of the liquid suspension of carbamazepine. Additionally, impaired cognition, exacerbations of focal seizures and asterixis have been reported in association with carbamazepine treatment. One case of a lingual-facial-buccal extrapyramidal reaction has also been described.
One study has suggested that gradual withdrawal of carbamazepine over ten days results in significantly fewer generalized tonic-clonic seizures compared to rapid withdrawal over four days.
One study has suggested that the epoxide metabolite of carbamazepine may be responsible for the occasional occurrence of seizure exacerbations in patients receiving carbamazepine.
Very common (10% or more): Dizziness (44%), somnolence (32%), ataxia (15%)
Common (1% to 10%): Headache, tremor
Uncommon (0.1% to 1%): Abnormal involuntary movements (tremor, asterixis, dystonia, tics)
Rare (less than 0.1%): Choreoathetotic disorders, orofacial dyskinesia, oculomotor disturbances, speech disorders (e.g., dysarthria or slurred speech), peripheral neuritis, paresthesia, paretic symptoms, neuroleptic malignant syndrome
Frequency not reported: Drowsiness, fatigue, taste disturbances
Rare (0.01% to 0.1%): A delayed multi-organ hypersensitivity disorder (of serum sickness type) with fever, skin rashes, vasculitis, lymphadenopathy, disorders mimicking lymphoma, arthralgia, leucopenia, eosinophilia, hepato-splenomegaly and abnormal liver function tests, occurring in various combinations, other organs may also be affected (e.g., lungs, kidneys, pancreas, myocardium, colon)
Very rare (less than 0.01%): Aseptic meningitis (with myoclonus and peripheral eosinophilia), anaphylactic reaction, angioedema
Frequency not reported: Multiorgan hypersensitivity reactions occurring days, weeks, or months after initiating treatment
Rash and pruritus often resolve after discontinuation of carbamazepine therapy. Both cases of lupus-like syndrome resolved after discontinuation of carbamazepine. Stevens-Johnson syndrome, erythema multiforme, and a mononucleosis-like syndrome have also been reported.
Alterations in liver function tests may progress to hepatotoxicity including cholangitis, granuloma formation, fever and hepatocellular necrosis. Discontinuation of carbamazepine often results in improvement in laboratory abnormalities and liver injury.
Very common (10% or more): Elevated gamma-GT (due to hepatic enzyme induction) usually not clinically relevant
Common (1% to 10%): Elevated alkaline phosphatase
Uncommon (0.1% to 1%): Elevated transaminases
Rare (0.01% to 0.1%): Cholestatic and hepatocellular jaundice, hepatitis of cholestatic, parenchymal (hepatocellular), or mixed type
Very rare (less than 0.01%): Granulomatous hepatitis, hepatic failure
Frequency not reported: Liver function test abnormalities, variegate porphyria, porphyria cutanea tarda
Very rare (less than 0.01%): Interstitial nephritis, renal failure, renal dysfunction (including albuminuria, hematuria, oliguria, and elevated BUN/azotemia)
Very rare (less than 0.01%): Pulmonary hypersensitivity (characterized by fever, dyspnea, pneumonitis or pneumonia), pulmonary embolism
Very common (10% or more): Allergic skin reactions, urticaria
Common (1% to 10%): Pruritus, rash, paresthesia
Uncommon (0.1% to 1%): Exfoliative dermatitis, erythroderma
Rare (0.01% to 0.1%): Systemic lupus erythematosus-like syndrome
Very rare (less than 0.01%): Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), photosensitivity, erythema multiforme, erythema nodosum, alterations in skin pigmentation, purpura, acne, sweating, alopecia, hirsutism, unusual bruising, pruritic and erythematous rashes, diaphoresis, onychomycosis, dermatitis
Frequency not reported: Psoriasiform eruption
Dangerous, sometimes fatal skin reactions (Stevens Johnson syndrome and toxic epidermal necrolysis), that can be caused by carbamazepine therapy are significantly more common in patients with the human leukocyte antigen (HLA) allele, HLA-B 1502. This allele occurs almost exclusively in patients with ancestry across broad areas of Asia, including South Asian Indians. Patients with ancestry from areas in which HLA-B 1502 is present should be screened for the HLA-B 1502 allele before starting treatment with carbamazepine. If these individuals test positive, carbamazepine should not be started unless the expected benefit clearly outweighs the increased risk of serious skin reactions. Patients who have been taking carbamazepine for more than a few months without developing skin reactions are at low risk of these events ever developing from carbamazepine. This is true for patients of any ethnicity or genotype, including patients who test positive for HLA-B 1502.
Common (1% to 10%): Diplopia, accommodation disorders (blurred vision)
Very rare (less than 0.01%): Lens opacities, conjunctivitis
Postmarketing reports: Diplopia, oculomotor disturbances, nystagmus, photosensitivity, visual hallucinations, scattered punctate cortical lens opacities, overall impairment of the chromatic and achromatic systems, increased intraocular pressure
Frequency not reported: Disorders mimicking lymphoma
Frequency not reported: Antibody deficiency, hypogammaglobulinemia
Postmarketing reports: Aseptic meningitis (with myoclonus and peripheral eosinophilia)
Common (1% to 10%): Abnormal thinking
Rare (0.01% to 0.1%): Hallucinations (visual or acoustic), depression, loss of appetite, restlessness, aggressive behavior, agitation, confusion, talkativeness
Very rare (less than 0.01%): Activation of psychosis, rebound mania following discontinuation of therapy
Frequency not reported: Euphoria, abuse
Euphoria has also been reported and has led to abuse of carbamazepine in some patients
Very rare (less than 0.01%): Sexual disturbances/impotence, abnormal spermatogenesis (with decreased sperm count and/or motility)
Frequency not reported: Urinary frequency, acute urinary retention, oliguria with elevated blood pressure, azotemia, albuminuria, glycosuria, elevated BUN, microscopic deposits in the urine
Common (1% to 10%): Hyponatremia, fluid retention, edema, weight gain, reduced plasma osmolarity due to an antidiuretic hormone (ADH)-like effect (leading in rare cases to water intoxication accompanied by lethargy)
Very rare (less than 0.01%): Elevated cholesterol (including HDL cholesterol), elevated triglycerides
Rare (0.01% to 0.1%): Muscle weakness
Very rare (less than 0.01%): Arthralgia
Frequency not reported: Osteoporosis, disturbances of bone metabolism (decrease in plasma calcium and 25-OH-cholecalciferol) leading to osteomalacia, decreased levels of plasma calcium
Common (1% to 10%): Vertigo
Very rare (less than 0.01%): Tinnitus, hyperacusis, hypoacusis, changes in pitch perception
Frequency not reported: Fever and chills
Medically reviewed by BestRx Medical Team Last updated on 1/1/2020.
Source: Drugs.com Carbamazepine