Understanding What is a Common PRN Psychotropic Medication

October 10, 2025 •

4 min read

An estimated 23 to 86 percent of hospitalized psychiatric patients receive pro re nata (PRN), or "as needed," psychotropic medications during their stay. So, what is a common PRN psychotropic medication? The answer often includes benzodiazepines like lorazepam and antihistamines like hydroxyzine, which are used to address acute symptoms like anxiety, agitation, and insomnia. This guide explores these medications, their uses, risks, and best practices for management.

Quick Summary

PRN psychotropic medications, such as lorazepam and hydroxyzine, are prescribed on an as-needed basis for acute symptoms like anxiety, agitation, and insomnia. Their use requires careful management due to potential side effects and risks like dependency, particularly with benzodiazepines. Clear communication and consideration of non-pharmacological alternatives are essential for effective treatment.

Key Points

Lorazepam is a common PRN benzodiazepine: Used for fast-acting relief of acute anxiety and agitation but carries a high risk of dependence.
Hydroxyzine is a common PRN antihistamine: Provides a sedative effect for anxiety and insomnia with less risk of dependence than benzodiazepines.
PRN medications are 'as needed': They address fluctuating or acute symptoms, unlike regularly scheduled medications.
Long-term PRN use has significant risks: Excessive use can lead to dependence, polypharmacy, and other adverse effects, and is associated with longer hospital stays and higher readmission rates in some patient populations.
Non-pharmacological interventions are crucial: Strategies like verbal de-escalation and environmental changes should be the first line of defense before administering PRN medication.
Clear documentation and regular review are essential: Prescribing and administration must be well-documented and periodically re-evaluated to ensure appropriateness and safety.

What Are PRN Psychotropic Medications?

PRN stands for the Latin phrase pro re nata, which means "as needed". PRN psychotropic medications are prescribed to provide rapid relief for acute, intermittent psychiatric symptoms that are not adequately managed by a patient's regularly scheduled medication regimen. This is particularly common in inpatient psychiatric settings where symptoms can fluctuate rapidly. The administration of these medications is typically at the discretion of a nurse, based on clear and documented indications from the prescribing physician.

The most common reasons for using PRN psychotropics include:

Acute Anxiety: Intense or sudden feelings of anxiety or panic.
Agitation: Restlessness, irritability, or aggressive behavior.
Insomnia: Difficulty falling or staying asleep related to underlying conditions.
Psychotic Symptoms: The emergent management of paranoia or hallucinations.

Benzodiazepines: A Common PRN Choice

Among the most widely prescribed PRN psychotropic medications are benzodiazepines, such as lorazepam (Ativan). These are known for their fast-acting effects on the central nervous system, producing a calming effect by enhancing the action of the neurotransmitter GABA.

Mechanism: Lorazepam binds to GABA receptors, which decreases neuron activity throughout the brain, providing rapid anxiety relief.
Indications: It is primarily used for acute agitation and anxiety.
Onset: The effects of lorazepam are typically felt within 30 to 60 minutes when taken orally.
Risks: A significant concern with benzodiazepines is their high potential for tolerance and dependence, which is why they are generally recommended for short-term use only. Long-term use can lead to addiction and cognitive impairment.

Antihistamines: A Milder Alternative

Hydroxyzine (Vistaril, Atarax), a sedating antihistamine, is another common PRN psychotropic medication, particularly when the goal is to avoid the dependency risks associated with benzodiazepines.

Mechanism: Hydroxyzine works by blocking histamine receptors in the brain, which causes a sedative and anxiolytic effect.
Indications: It is often used for anxiety relief and for managing insomnia related to anxiety.
Onset: It acts relatively quickly, with effects beginning within a short time of administration.
Risks: While less risky than benzodiazepines, hydroxyzine can cause significant drowsiness, dry mouth, and cognitive impairment, especially in elderly patients. Tolerance to its sedative effects can also develop over time.

Important Considerations for PRN Medication

Using PRN psychotropic medication requires careful attention to both the immediate symptomatic relief and the broader implications for a patient's long-term health. Over-reliance on PRN medication can sometimes mask underlying issues that need more comprehensive treatment.

Risks of Long-Term Use

Excessive use of PRN psychotropics, especially benzodiazepines, carries several risks:

Dependence and Withdrawal: Prolonged use can lead to physical dependence, resulting in withdrawal symptoms if stopped abruptly.
Antipsychotic Polypharmacy: Studies show that PRN psychotropic use can be associated with higher rates of receiving multiple antipsychotic drugs, potentially complicating treatment.
Cognitive Effects: Some medications can cause long-term cognitive impairment, affecting memory and concentration.

Alternatives and Best Practices

Best practices for managing acute behavioral and psychological symptoms often involve integrating non-pharmacological interventions with medication.

Non-Pharmacological Strategies: Techniques like verbal de-escalation, creating a calm environment, offering distraction, and employing sensory modulation can often prevent the need for medication.
Clear Documentation: Prescribing practitioners should provide clear, specific indications for PRN use, and nurses must document the exact behavior or symptom that led to the medication's administration.
Regular Review: All PRN orders should be regularly reviewed to determine if the medication is still necessary and effective, or if the underlying condition requires adjustment of the patient's regular medication regimen.

Comparison of Common PRN Psychotropics


Feature	Lorazepam (Benzodiazepine)	Hydroxyzine (Antihistamine)
Drug Class	Benzodiazepine	First-Generation Antihistamine
Primary Use	Acute anxiety and agitation	Anxiety and insomnia
Speed of Action	Fast-acting	Relatively fast-acting
Addiction Potential	High potential for tolerance and dependence	Lower potential, but can lead to tolerance to sedative effects
Common Side Effects	Drowsiness, dizziness, loss of coordination, confusion	Drowsiness, dry mouth, blurred vision
Patient Population	Used with caution in the elderly due to risk of sedation and cognitive impairment	Used with caution in the elderly; on the list to avoid in older adults due to side effects

Conclusion

Understanding what is a common PRN psychotropic medication is vital for safe and effective mental health care. While drugs like lorazepam and hydroxyzine can be crucial tools for managing acute symptoms, they are not without risk. Prescribers, nurses, and patients must work together to ensure PRN orders are used appropriately, sparingly, and with clear purpose. Emphasizing non-pharmacological strategies, conducting regular reviews of PRN needs, and educating patients on risks are essential best practices. By doing so, healthcare providers can maximize patient safety and promote long-term stability rather than relying solely on reactive treatment.

For more information on psychotropic medications, including lorazepam, the National Alliance on Mental Illness (NAMI) is an excellent resource: Lorazepam (Ativan).

Frequently Asked Questions

PRN stands for the Latin phrase pro re nata, which translates to "as needed".

Lorazepam (brand name Ativan) is one of the most commonly prescribed benzodiazepines for PRN use to manage acute anxiety and agitation.

Hydroxyzine is a sedating antihistamine that is sometimes used to manage anxiety and insomnia, and it is preferred by some clinicians to avoid the high risk of tolerance and dependence associated with benzodiazepines.

Common side effects vary by medication but can include drowsiness, dizziness, confusion, dry mouth, and weight gain, especially with benzodiazepines and sedating antihistamines.

Long-term use, especially with benzodiazepines, can lead to dependence, withdrawal symptoms, and increased risks of cognitive changes, metabolic issues, and other adverse effects.

Documentation should clearly state the specific behavior or symptom that prompted the medication's administration, rather than vague terms like 'agitation'.

Yes, best practices recommend trying non-pharmacological interventions like verbal de-escalation, distraction, or other behavioral strategies before resorting to medication.