2. A 25-year-old woman goes to the hospital emergency room and reports having symptoms of schizophrenia. After examining the patient, the doctor determines that the symptoms are not because of schizophrenia but rather the result of a drug that has similar effects. Which of the following drugs is most likely to have caused the patient's symptoms?
Answer: B
A dopamine agonist, such as amphetamine
Dopamine agonists, such as amphetamine, can lead to symptoms that mimic schizophrenia due to their stimulation of dopamine receptors in the brain. This overstimulation can result in hallucinations and delusions, which are characteristic symptoms of schizophrenia.
A) An opioid antagonist, such as naloxone
An opioid antagonist like naloxone does not typically cause symptoms resembling schizophrenia. Instead, it is used to reverse the effects of opioid overdose and can induce withdrawal symptoms in opioid-dependent individuals but does not affect dopamine pathways in a manner that would produce psychotic symptoms.
B) A dopamine agonist, such as amphetamine
Dopamine agonists, such as amphetamine, are known to increase dopamine activity in the brain, which can lead to psychotic symptoms similar to those of schizophrenia. Therefore, this option accurately reflects the cause of the patient's symptoms in this scenario.
C) Birth control pills that contain estradiol or other types of estrogen
Birth control pills containing estrogen do not generally produce symptoms akin to schizophrenia. While hormonal changes can affect mood and may lead to various psychological effects, they are unlikely to cause the acute psychotic symptoms described in this case.
D) An antipsychotic drug that is a dopamine antagonist
Antipsychotic drugs that are dopamine antagonists are designed to alleviate symptoms of schizophrenia rather than induce them. Therefore, this option cannot be the cause of the patient's symptoms, as these medications work by blocking dopamine receptors.
Conclusion
The correct answer, a dopamine agonist such as amphetamine, is the most likely cause of the patient's symptoms, as it directly stimulates dopamine pathways in a way that can produce psychotic features. The other options fail to align with the mechanism that leads to the presentation of symptoms similar to schizophrenia, making them incorrect in this context.