Approach to benzodiazepine and barbiturate use, intoxication, and overdose: Clinical sciences

Chapters:

Watch video only

Introduction0:00–1:07

Benzodiazepines and barbiturates are two common types of sedatives and anxiolytics typically used to treat panic disorder, anxiety disorders, and insomnia.
Both classes bind to gamma-aminobutyric acid, or GABA, receptors and increase the affinity of the receptor to bind to GABA, a primary inhibitory neurotransmitter.
This results in an inhibitory effect within the central nervous system by reducing neuronal excitability. This process produces symptoms of sedation by preventing overstimulation of the brain.
Both benzodiazepines and barbiturates have addictive properties, which can lead to chronic dependance, misuse and overuse.
Of the two, benzodiazepines are more commonly used in clinical settings. Barbiturates, on the other hand, are no longer used as often due to their narrow therapeutic window and ease of overdose.
Keep in mind that illicit use of these medications without a legitimate prescription is common. Alright, when a patient presents with a chief concern suggestive of benzodiazepine or barbiturate use, first perform an ABCDE assessment to determine if they are stable or unstable.

Unstable Patient1:07–4:30

Your goal here is to determine if the patient is actively experiencing an overdose which is a medical emergency. If the patient is unstable, stabilize their airway, breathing, and circulation right away.
Provide supplemental oxygen and have a low threshold for endotracheal intubation. Make sure to assess for the Glasgow Coma Scale, or GCS.
If the GCS score is less than 8, intubation is indicated. Additionally, obtain IV access and consider starting IV fluids.
Then, continuously monitor vital signs including temperature, heart rate, blood pressure, respiratory rate, oxygen saturation, and cardiac telemetry.
Lastly, consider using cooling blankets if the patient is hyperthermic. Next, perform a focused history and physical and order a urine and/or a serum toxicology screen.
If the patient is unable to communicate, obtain history from a family member or a friend accompanying the patient. History will often reveal a recent or chronic use of benzodiazepine or barbiturate.
For patients with recent use, try to determine how much of which drug was ingested and when. The amount and timing of ingestion is important when anticipating the acute clinical course of the patient.
For example, if the patient ingested a large amount shortly before the presentation, you can expect the symptoms to get worse as the substances continues to be absorbed.
On exam, you might see altered mental status ranging from confusion to stupor to a coma. If the patient is awake and alert, they might show signs of hallucinations, psychosis, or anterograde amnesia.
One important exam finding to look for is severe respiratory depression, defined as respiratory rate of 8 or below. This is an ominous sign for respiratory collapse which can quickly lead to death if not addressed.
Additional findings you might see are ataxia, nystagmus, hypotonia, or hyporeflexia. With these findings, diagnose benzodiazepine or barbiturate overdose.
Although clinical findings are enough to make the diagnosis of overdose and start intervention, toxicology screening will help identify the causative agent.
However, you should never wait for the tox screen results to start your treatment! Now, the management of confirmed benzodiazepine or barbiturate overdose is mostly supportive.
This includes providing supplemental oxygen or mechanical ventilation, IV fluids, and other symptom management. Flumazenil may be administered, but should be used with caution, as it can precipitate withdrawal symptoms and seizures.
The goal is to support respiratory and circulatory function until the body clears out the substance. Time for a high-yield fact!
Flumazenil can be specifically used in benzodiazepine overdose as an antidote to reverse the effects, but it does not reverse the effects of a barbiturate overdose!
Now that we’ve taken care of the unstable patients, let’s talk about the stable ones. Your next step here is to obtain a focused history and physical exam and order a toxicology screen.

Stable Patient/ Benzodiazepine/barbiturate intoxication4:30–6:04

If the patient has a history of recent benzodiazepine or barbiturate use, and presents with gait ataxia, slurred speech, mildly reduced heart rate and blood pressure, consider benzodiazepine or barbiturate intoxication.
To confirm, assess the DSM-5 criteria. The patient must have 1 or more of the following: recent use of either a benzodiazepine or barbiturate; mood or behavioral problems resulting from the substance use; and one or more symptoms of intoxication.
These include incoordination, dysarthria, nystagmus, impaired memory, or gait disturbance. If the patient meets these criteria, diagnose benzodiazepine or barbiturate intoxication.
Management involves supportive care, supplemental oxygen therapy, and possibly administration of flumazenil. Keep in mind, flumazenil may precipitate withdrawal symptoms and seizures if the patient is a chronic benzodiazepine user or has an underlying seizure disorder.
Time for a clinical pearl! Toxicology screen is often obtained for stable patients to confirm the substance and to look for other substances the patient might have taken.
However, it is not required to make the diagnosis. Now that we’ve talked about the acute use of benzodiazepine and barbiturates, let’s discuss chronic use of these substances.

Benzodiazepine/barbiturate use disorder6:04–8:23

History might reveal a chronic condition, like anxiety, panic disorder, or insomnia for which benzodiazepine was prescribed as treatment.
On the other hand, the patient might have a history of illicit use of benzodiazepine or barbiturates, and in some cases chronic use of other substances like stimulants, alcohol, or other central nervous system depressants.
On exam, you might find slurred speech, but these individuals often have normal pulse and blood pressure. These findings should lead you to consider benzodiazepine or barbiturate use disorder.
Then, assess using the DSM-5 to confirm your diagnosis. According to the DSM-5, your patient must have two or more of the following findings observed within the past twelve months: tolerance as evidenced by increasing doses to achieve the desired effect; withdrawal symptoms when not taking the substance; cravings to use; using more than intended; difficulty stopping or reducing use; spending significant time devoted to substance use; use despite understanding health problems from the substance; use despite adverse consequence; neglecting other responsibilities or activities due to substance use; or risky or dangerous behaviors and situations due to substance use.
If the patient meets the criteria, diagnose benzodiazepine or barbiturate use disorder. Management involves supportive care and psychotherapy like cognitive behavioral therapy.
Here’s a clinical pearl! Some patients with chronic benzodiazepine or barbiturate use disorder might benefit from inpatient rehabilitation or intensive outpatient therapy.
Keep in mind, abrupt cessation of benzodiazepine or barbiturates can cause acute withdrawal symptoms. Therefore, slow taper over a few weeks is often a better choice to avoid withdrawal.
Also, for the first days to weeks, patients should be monitored closely for withdrawal and appropriate supportive care should be offered.
Lastly, let’s talk about benzodiazepine and barbiturate withdrawal. Patients who are in withdrawal often present after a recent cessation of taking benzodiazepine or barbiturate.

Benzodiazepine/barbiturate withdrawal8:23–10:02

On exam, you might see diaphoresis, nausea, vomiting, and even tachycardia, seizures, tremors, or memory impairment in severe cases.
Symptoms can vary depending on the dose the patient is used to taking and the duration of abstinence. In other words, patients who have been taking large amounts can be expected to have more severe withdrawal symptoms.
If any of these features are present, you should consider benzodiazepine or barbiturate withdrawal. To confirm, assess the patient using the DSM-5 criteria.
You should assess for the presence of two or more of the following features within hours to days of their last use. These include no or reduced use after prolonged heavy substance intake; anxiety, dysphoria, irritability; insomnia; tachycardia, hypertension; muscle tension, muscle tremor; myalgias; arthralgias; or hallucinations.
If the patient meets these criteria, diagnose benzodiazepine or barbiturate withdrawal. Management involves supportive care, psychotherapy such as cognitive behavioral therapy, and a gradual taper using long-acting benzodiazepine or barbiturate formulations.

Review10:02–10:51

Alright, as a quick recap... Benzodiazepines and barbiturates are commonly used sedatives that can cause overdose, intoxication, chronic use, and withdrawal.
Unstable patients experiencing overdose need urgent supportive care. When it comes to stable patients, if they used these medications recently, you are probably dealing with acute intoxication, which is managed with supportive care.
In benzodiazepine or barbiturate use disorder, patients often have signs of dependance and chronic use over the last twelve months.
These patients need supportive care and psychotherapy. Finally, withdrawal can present within hours to days of last substance use.
Management includes supportive care, psychotherapy, and taper therapy.
Approach to benzodiazepine and barbiturate use, intoxication, and overdose | Osmosis