Carbamazepine Side Effects
Carbamazepine or CBZ is a mood stabilizing and anticonvulsant drug used in the treatment of bipolar disorder and epilepsy. It is available in different brand names such as Equetero, Epitol, Carbatrol and Tegretol.
Uses of Carbamazepine
Carbamazepine is primarily used for the treatment of seizure disorders. It is also used in the treatment of neuropathic pain such as trigeminal neuralgia because of its ability to stabilize the pain signals in the brain thereby limiting pain sensations. Carbamazepine is used as a second line management for bipolar disorder. It may also be used in the management of schizophrenia as adjunct to antipsychotic medications.
Other uses of carbamazepine include as a management for attention deficit hyperactivity disorder, phantom limb sensation, paroxysmal extreme pain, complex regional pain syndrome, neuromyotonia, borderline personality disorder, intermittent explosive disorder and post traumatic stress disorder.
Carbamazepine side effects
The carbamazepine side effects are due to the action of carbamazepine do the neurons. Carbamazepine stabilizes the inactivated sodium channels leading to reduced sodium channels that will be available for the formation of action potentials in the brain. The sodium channels are responsible for allowing the brain cells to generate action potentials. With the action of carbamazepine, the brain cells are less excitable.
Carbamazepine was also found to potentiate GABA receptors that increases the binding of Gamma Amino Butyric Acid, an inhibitory neurotransmitter, thereby reduces mania of clients. These mechanisms of carbamazepine are also responsible to the various carbamazepine side effects. Carbamazepine side effects include:
1. Drowsiness
The reduced excitability of the brain cells leads to slowing down of nerve impulses in the brain leading to drowsiness.
2. Dizziness and unsteadiness
The cerebellar functioning may also be slowed leading to problems in coordination as carbamazepine side effects.
3. Upset stomach
Nausea and vomiting may be experienced by patients taking carbamazepine as carbamazepine side effects. Stomach pains may also result, which may be related to gastric irritation.
4. Impairment in motor coordination
The nerve impulses to the motor cortex from the brain may also be limited leading to problems in motor abilities. This may be managed using vitamin B 12 to improve nerve impulse transmission in the peripheral areas of the body; however, watch out for possible B12 side effects.
5. Cardiac arrhythmias
The sodium channels in the myocardium may also be affected leading to affectation in the action potentials in the heart.
6. Vision problems
Patients taking carbamazepine may also experience double or blurring of vision as carbamazepine side-effects due to slowing of the transmission of nerve impulses from the optic nerve to the brain.
7. Hyponatremia
Reduction in the blood level of sodium is a rare carbamazepine side effect due to limitation of the influx of sodium from the cells into the blood.
8. Reduction in blood cells such as platelets
The reduction in platelets is a life-threatening carbamazepine side effect. Patients receiving carbamazepine require frequent blood tests during the first few months of therapy to monitor the complete blood count of patients. Easy bruising and bleeding may indicate low levels of platelets.
9. Hypothyroidism
Carbamazepine may also cause exacerbation of hypothyroidism as a carbamazepine side effect as a result of slowing of the regulation of the pituitary gland to the production of thyroid stimulating hormone due to slowed nerve impulse transmissions in the brain. Yearly thyroid function tests may be necessary to monitor the thyroid function.
10. Problems in hearing
The otic nerve may also be affected leading to disturbed perception of sounds. Patients often experience a lower tone than before. This carbamazepine side effect is usually relieved once carbamazepine is discontinued.
11. Cognitive anomalies
Problems in cognition may also be experienced because of slowing of the action potentials as manifested by slowing of EEG tracings.
12. Skin rashes
Presence of skin rashes may be a sign of hypersensitivity reaction to carbamazepine or as an initial sign of Steven Johnson syndrome, a skin condition resulting in intake of medications.
Despite the vast carbamazepine side effects, it is still prescribed to patients needing it. People should ensure precaution and adhere to the prescription of the physician in order to achieve desired results as well as preventing carbamazepine side effects. Regular monitoring of patients is also essential in order to identify serious carbamazepine side effects.