Benzodiazepines

Benzodiazepines are an older category of medications that have many therapeutic uses. This module breaks down several, including treatment for relief of anxiety, skeletal muscle spasm and spasticity, seizure disorders, emergency treatment of status epilepticus, acute alcohol withdrawal, and as an anesthetic agent during moderate sedation.

Prototype and Other Medications

Because this lesson is focusing on medications that treat anxiety, the prototype medications are diazepam and alprazolam. You can find benzodiazepines that providers prescribe for one of the other previously described uses in different sections of this module. Other benzodiazepines that treat anxiety disorders include lorazepam, chlordiazepoxide, clorazepate, and oxazepam.

Expected Pharmacologic Action

Benzodiazepines fall into the CNS depressant category of medications. They enhance the inhibitory effects of the transmitter gamma-aminobutyric acid, or GABA. A benzodiazepine’s action as an anxiolytic, or medication that treats anxiety, relates to its ability to act on the limbic system. The limbic system is a network of neurons and neurotransmitters (norepinephrine, serotonin, and dopamine) that relate to the perception and expression of emotions.

Adverse Drug Reactions

Adverse effects of benzodiazepines include dizziness, drowsiness and lethargy due to the CNS effects of these medications. Impaired recall of events can occur in clients on very high doses or when used in combination with alcohol. A paradoxical reaction of confusion and anxiety is another possible effect, especially in older adults. It’s important to monitor vital signs because these medications can also cause hypotension, tachycardia, and respiratory depression. This is rare with oral administration but poses a risk with IV administration.

Sedative effects tend to diminish within 7 to 10 days. Tolerance can develop over a period of weeks, which may require an increase in dosage to achieve the original effects. Overdose or toxicity of oral benzodiazepines can cause possibly life-threatening sedation, hypotension, respiratory depression, and cardiac arrest. For clients who do develop a physical dependence, withdrawal is usually mild if they take the medication at therapeutic doses. But if clients misuse the medication with significantly larger doses, withdrawal can cause intense symptoms. Benzodiazepines should be used cautiously in clients with a predisposition to misuse.

Safety Alert

Stopping benzodiazepines abruptly can cause possible withdrawal manifestations. These manifestations can include insomnia, anxiety, tremors, diaphoresis, dizziness, panic, hypertension, seizures, paranoia, muscle twitching, and even hallucinations. Instruct clients to follow the provider’s directions on decreasing the dosage gradually.

Interventions

When clients are taking benzodiazepines, it’s essential that you help prevent falls and other injuries following administration. Evaluate their memory and watch for a paradoxical reaction, especially in older adults. Monitor vital signs, especially with IV administration. Check for manifestations of tolerance and dependence. When discontinuing the medication, it’s crucial to taper the dosage over 1 to 2 weeks to prevent or minimize withdrawal. As you do this, make sure to watch for manifestations of withdrawal. For clients experiencing and overdose, reverse sedation with IV flumazenil. Flumazenil is a benzodiazepine receptor antagonist.

Safety Alert

Manage overdose with supportive measures based on findings. The benzodiazepine antidote, flumazenil, can be administered as an adjunct in management of toxicity or overdose of benzodiazepines (may induce seizures in clients with a history of seizure disorders or who are on tricyclic antidepressants).

Administration

When administering benzodiazepines for their anxiolytic actions, be aware that alprazolam is only available in oral form. If clients taking oral benzodiazepines develop gastrointestinal manifestations, instruct them to take the medication with food. Diazepam is available for oral, rectal, intramuscular, or IV administration. Use the IM and IV routes in emergent situations only because severe reactions, such as respiratory arrest, can occur. Be aware that IV diazepam precipitates in solution with some diluents and medications. Administer the emulsion form IV only, not IM. Giving diazepam IM can result in inconsistent absorption. So, if you must use that route, inject the medication slowly into a large muscle. If you must administer IV diazepam, do it slowly and have emergency resuscitation equipment nearby.

Safety Alert

Always check the patency of the IV line prior to administering diazepam IV. Injection may cause burning and venous irritation; avoid small veins. Assess the IV site frequently during administration; diazepam may cause phlebitis and venous thrombosis.

Client Instructions

Make sure that clients taking benzodiazepines use care with ambulation and when driving or participating in activities that require mental alertness. Amnesia may occur if taking high doses or combined with alcohol. Inform clients of possible paradoxical effects of the medication, such as insomnia or heightened anxiety, and instruct them to notify the provider if they occur. Caution clients to avoid increasing the prescribed dose. Make sure they know to change positions slowly to prevent falls. Explain that tolerance to benzodiazepines occurs with time, so clients taking them for long-term management of anxiety need to taper the medication slowly to prevent or minimize withdrawal manifestations. Clients taking benzodiazepines should avoid the ingestion of alcohol or other CNS depressants due to the possibility of potentiating the CNS depressant effects of both medications.

Contraindications and Precautions

Use caution when administering benzodiazepines to older adults, children under the age of 18, and clients with renal or hepatic impairment, mental health disorders, suicidal ideation, chronic respiratory disorders, or neuromuscular disorders. Most of these precautions exist in relation to the CNS depression that benzodiazepines cause. These medications are also a poor choice for clients prone to addiction. Benzodiazepines are schedule IV controlled substances, so prescription and access are limited. They are contraindicated in clients with glaucoma, clients in a coma or shock, in neonates, and in labor and delivery situations. Benzodiazepines are a teratogenic medication.

Safety Alert

Advise clients to stop taking benzodiazepines immediately if they become pregnant and tell them to notify their provider. Benzodiazepines are teratogenic, so they are also contraindicated for clients who are lactating.

Interactions

Don’t give benzodiazepines with other CNS depressants, such as alcohol, opioids, and other benzodiazepines, due to the increased risk of severe sedation and respiratory depression. Cimetidine can increase benzodiazepine levels, and smoking can decrease the effect of benzodiazepines. The herbal supplements kava-kava, chamomile and valerian increase the risk for sedation. And disulfiram and fluoxetine increase alprazolam levels.

Medication Information Table: Benzodiazepines

Click to download this Medication Information Table.

diazepam

Classification: Benzodiazepines

Therapeutic use: Treats anxiety and anxiety disorders, skeletal muscle spasm and spasticity, seizure disorders, status epilepticus, acute alcohol withdrawal manifestations and is used in the induction of anesthesia.

alprazolam Classification: Benzodiazepines Therapeutic use: Primarily used to treat anxiety disorders, panic disorders, and insomnia; it may also be used as a premedication for medical procedures.