Question

Multiple-choice question: A patient with mixed mania is prescribed carbamazepine (Tegretol). Th e nurse should instruct the patient that toxic side eff ects can occur if they concurrently take a medication such as: Exercise 3.52 A. Lithium B. Amoxicillin C. Cimetidine D. Buspirone

Short answer

The correct answer is C. Cimetidine as concurrent usage can lead to toxic side effects by increasing the levels of carbamazepine.

Step-by-step solution

Understand the pharmacology of carbamazepine

Carbamazepine (Tegretol) is an anticonvulsant and mood-stabilizing drug. It is commonly used to treat a variety of conditions, including bipolar disorder, epilepsy, and neuropathic pain.

Evaluate potential drug interactions

Next, consider possible drug interactions between carbamazepine and the other medications listed. The medications to consider are Lithium (used in the treatment of bipolar disorder), Amoxicillin (an antibiotic), Cimetidine (an anti-acid), and Buspirone (an anti-anxiety medication).

Determine the correct answer

Upon reading about the pharmacology of these drugs, one can see that concurrent use of carbamazepine and Cimetidine can lead to increased levels of carbamazepine in the body, potentially leading to toxic side effects. Therefore, the correct answer is C. Cimetidine.

Key concepts

Carbamazepine Drug Interactions

Understanding how carbamazepine interacts with other medications is crucial for patient safety. Carbamazepine, commonly known under the brand name Tegretol, serves as an anticonvulsant and mood stabilizer.

It is important to be aware that carbamazepine can both affect and be affected by various other drugs, leading to changes in its concentration within the blood. For example, medications such as cimetidine, an antacid used to treat ulcers and gastroesophageal reflux disease, can inhibit the metabolism of carbamazepine, increasing its levels potentially to toxic concentrations.

Other substances like grapefruit juice can also affect the metabolism of carbamazepine. Conversely, carbamazepine is known to induce certain liver enzymes, which can accelerate the breakdown of other medicines, which may result in decreased effectiveness of those drugs. Examples include certain antidepressants, antipsychotics, oral contraceptives, and warfarin, an anticoagulant.

It's important for healthcare providers to regularly review a patient's full medication list for potential interactions.

Mixed Mania Treatment

Mixed mania refers to a state where symptoms of mania and depression occur simultaneously in patients with bipolar disorder. Treatment can be challenging and often requires a combination of pharmacological and psychological interventions.

Carbamazepine is commonly used in the treatment due to its mood-stabilizing properties, but it's not the only option. Other mood stabilizers include lithium and valproic acid. Antipsychotic medications might also be used adjunctively.

When treating mixed mania, it's critical to avoid medications that could exacerbate certain symptoms or contribute to a 'switch' in mood states. Avoiding antidepressants that could accelerate mania or choosing the right mood stabilizer requires careful consideration. Monitoring for drug interactions, as previously mentioned, forms an essential part of this treatment process.

Nursing Responsibilities

Nurses play an integral role in managing patients on medications like carbamazepine. They must be diligent in educating patients about potential side effects, recognizing symptoms of toxicity, and understanding drug interactions.

Educating the patient includes advising them on which substances to avoid, such as grapefruit juice and certain over-the-counter drugs like cimetidine. Furthermore, nurses should ensure patients understand the importance of adherence to their prescribed regimen and regular monitoring, such as blood tests to check carbamazepine levels.

Monitoring for Adverse Effects

Regular assessments for signs of toxicity, such as dizziness, double vision, or significant changes in mood or behavior, are necessary.

Multidisciplinary Collaboration

Communication with other healthcare professionals, providing updates on the patient's condition, and making necessary adjustments to treatment plans is also a key nursing responsibility.