Response To Carbamazepine Anticonvulsant

Mrs. Dey reported she had been extremely sick with the anti-seizure medications and her primary care advised her to stop the current medication and go into the hospital. She was hospitalized overnight in observation and Dr. Hardy requested she come into his office the following Monday, September 11, 2017. Due to the unexpected appointment, I had a scheduling conflict and my colleague Laurie Wawrzynaik RN, BSN, MA, attended.

Lorazepam binds to an allosteric site on GABA-A receptors, which are pentameric ionotropic receptors in the CNS. Binding potentiates the effects of the inhibitory neurotransmitter GABA, which upon binding opens the chloride channel in the receptor, allowing chloride influx and causing hyperpolerization of the neuron.

Gabapentinoids are analogues of gamma-aminobutyric acid (GABA). They bind to the α2δ subunit of the calcium channels on neurons. Both of them have a relatively benign side effect profile, lack significant drug interactions, are not liver metabolized, and are renally excreted. Pregabalin has quicker absorption and higher absolute bioavailability compared to gabapentin.1

Status epilepticus are seizures lasting >20 minutes, or repeated seizures without regaining consciousness [71]. Physicians should be particularly careful with it, since the background may be other than epilepsy. Infection, haemorrhage, trauma, hypoxia, ischemic or haemorrhagic stroke, hypoglycaemia, hyponatremia, drug toxicity and alcohol withdraw should be ruled out. In any of the above, the provoking cause should be treated. If the cause is epilepsy, the treatment of choice is benzodiazepines and the second choice is phenytoin/ fosphenytoin, but with caution as rapid infusion may induce cardiovascular problems. For resistance in those two drugs, the Neurocritical Care Society’s Status Epilepticus Guideline

Tamazepam acts at many levels in the CNS, producing generalized depression. Effects may be mediated by GABA, an inhibitory neurotransmitter.

While the codeine is what caused the CNS depression that threatened our patient, it should be noted that the ineffectiveness of his SSRI he spoke of in our review of systems may also be attributed to our patient’s possible status as an ultra-metabolizer. Fluoxetine, fluvoxamine, and paroxetine are influenced by a few genes of the CYP450 enzymes but none more than CYP2D6. The ultra-metabolizer phenotype of CYP2D6 causes the patient to have sub-therapeutic concentrations of SSRIs causing decreased response.

Pregabalin, trade name Lyrica, approved for its anticonvulsant properties and to relieve pain in those who suffer from diabetic neuropathy. The chemical structure of pregabalin is structurally analogous to γ-aminobutyric acid (GABA), an inhibitory neurotransmitter found in the central nervous system and functions by binding to α2δ voltage-gated calcium ion channel in presynaptic, inhibiting the release of neurotransmitters, most notably GABA. By decreasing the amount of the inhibitory neurotransmitter GABA in synaptic terminals, epileptic seizures can be controlled and prevented.1

The study by Amato, Minozzi and Davoli (2011) examined five randomized controlled trials to find an efficient and safe medication to treat AWS. The study which had a total of 7333 patients concluded that benzodiazepines were better for controlling seizures when compared to a placebo and antipsychotics (Amato et al., 2011). When comparing benzodiazepines versus anticonvulsants, researchers concluded that the benzodiazepine chlordiazepoxide had better outcomes. No other studies were found which would compare the effectiveness among benzodiazepines for the treatment of AWS.

Gamma-Aminobutyric acid commonly referred to as GABA, and glutamate make up around 80 percent of the neurotransmitters found in brain. GABA dampens the activity in the brain while

Chronic intake, delayed onset of action, drug resistance and numerous side effects of current antidepressants have forced researchers to look for new and safer drugs (1, 2) with rapid onset and longer acting times.

It’s also limiting the influx of sodium in across the cell membranes. Carbamazepine also stimulates the release of antidiuretic hormone by promoting it actions to increase the reabsorptions of water. Majorly the prescribing of carbamazepine is to treat the epilepsy. Epilepsy is characterized by long term propensity of recurrent seizures. Seizures are the abnormal electrical activity in the brain and it is a symptom of epilepsy, but not all epilepsy is characterized by seizures. There is no cure for epilepsy but the seizures can be controlled with anti convulsant drugs. [WebMD, 2017] The drug should be taken with food according to the dosage that prescribe by physicicans and the people with hypersensitivity, blockage of atrioventricular and the patient with depression of bone marrow history should not take this drugs. The adverse drugs reactions are dizziness, fatigue, drowsiness, nausea, vomiting, headache, dry mouth. The side effect might subside within hours but if not subside the patient should immediately seek medical attention. This drug also can interfere with contraceptive hormonal. [Medlineplus,

In the study patients age 20 to 64 that is diagnosed with depression and on antidepressants was used to observe the possibility of antidepressants causing epilepsy. The data does show some links between antidepressant use and epilepsy, even though it is inconsistent and non-decisive.

Cross-tolerance is an occurrence in which an individual with resistance to a particular drug’s effect gains tolerance towards another drug. This majorly happens in situations whereby both drugs have similar effects e.g. both drugs may perform and have effect on the same cell receptors, they may also affect specific transmission of particular neurotransmitters. The objective aim of the experiment is to evaluate and determine the drug cross tolerance in different mice, by speculation of the level and intensity of sedation induced by pentobarbitone at various doses which will be given to a group of control mice with no drug exposure and a group of mice pre-treated with TCPOBOP 24 hours before. Barbiturates are CNS depressant that initiate the loss of righting reflex, pentorbarbitone acts on GABA-A receptors which are ligand gated

Anticonvulsants have an edge with rapid-cycling and mixed mood states (e.g. depression with racing thoughts). Except for gabapentin (Neurontin) and lamotrigine (Lamictal), they require blood tests. Carbamazepine (Tegretol) is monitored with blood levels; also CBC, platelets and liver function tests. Valproate (Depakote) requires CBC, platelet count and liver function tests; blood levels may be helpful. Lamotrigine (Lamictal) requires caution because of its association with a rare but dangerous skin rash (exfoliative dermatitis); risk can be minimized by starting with low doses and increasing gradually. Use lower doses with medications that slow lamotrigine metabolism (e.g. valproate). Gabapentin is generally safe and does not require blood tests.

Treatment for epilepsy is often focused on controlling the seizures with the least amount of medication as possible. Antiepileptic drugs (AEDs) are the class used to accomplish this. Some of the AEDs that are used most often are Clonazepam, Diazepam, Divalproex, Gabapentin, and Phenytoin. The most common side effects of these medications include nausea, vomiting, sedation, fatigue, and lethargy. (Kwan,1; Benbadis, 3-5; Huethers,637)