Overview

Nightmare disorder, a sleep disorder, causes significant stress and interference in daily life.¹ Several treatments have been shown to help this condition.

If you are struggling to find evidence-based medication options that are best for you, then you have come to the right place. This article will walk through prazosin and other treatments that could be effective in the treatment of nightmare disorder.

What is nightmare disorder?

Nightmare disorder is a disorder that affects sleep by frequent, vivid nightmares, leading to stress and impacting daily life, impairing both work and social commitments.¹ These nightmares can often cause insomnia, tiredness, difficulty concentrating and lack of energy.¹

These nightmares can come with symptoms such as: sweating, shortness of breath and feelings of fear, anger, shame and sadness.¹ These symptoms can happen both during and after the nightmares.¹

There are 2 main types of nightmares: idiopathic and posttraumatic.¹ Idiopathic nightmares are creative and imaginary in nature, while post-traumatic nightmares can be based on traumatic feelings or direct replication of a traumatic event the individual has experienced.¹

Nightmare disorder can often present as a symptom of a mental disorder, such as anxiety or post-traumatic stress disorder (PTSD)¹. It is important to manage this disorder as it can affect essentially all aspects of life.¹

How do we treat nightmare disorder?

Nightmare disorder can persist for decades if not treated, so it is important to do so for individual health.¹

There are several approaches to treating nightmare disorder, including psychodynamic approaches, which find the meanings of the nightmares, desensitisation and exposure therapy and pharmacological therapies, which are medications used, such as prazosin used to treat this disorder.¹

Prazosin: the primary pharmacological treatment for nightmare disorder

How does prazosin work?

Prazosin is an alpha-1 adrenoreceptor antagonist that can be used to treat nightmare disorders as well as high blood pressure.^1,3 In particular, it is associated with PTSD-related nightmares^1,2. It works by modulating the noradrenergic system, which plays an important role in the body’s stress response.²

In PTSD, the sympathetic nervous system is overactivated, leading to increased levels of noradrenaline, which is a neurotransmitter involved in the body’s fight or flight response.² The heightened level of noradrenaline caused by PTSD is what is believed to be contributing to and causing PTSD-related nightmare disorder.²

Prazosin works by blocking alpha-1 adrenergic receptors in the nervous system, which cause smooth muscles to relax, decreasing blood pressure.^2,3

Prazosin also crosses the blood-brain barrier and decreases the effects of noradrenaline on the nervous system, which decreases the symptoms of PTSD and, therefore, nightmare disorder². 

Prazosin administration

Prazosin is a medication taken by mouth and comes in capsule form.³ In PTSD-related nightmare disorder, it is taken on a nightly basis.³ While this medication has been shown to help nightmare disorder symptoms, there can be some serious side effects, including: low blood pressure, fainting, nausea, and dizziness.^2,3

Are the effects of prazosin on nightmare disorder scientifically proven?

A review found that prazosin significantly reduces the severity and frequency of nightmares associated with PTSD, though the evidence base is limited².

There was also a clinical trial done on military personnel with chronic PTSD, with nightmares being a symptom they experienced.⁴ This clinical trial did not show any statistical significance in alleviating nightmares.³

Although some studies showed prazosin's effectiveness in alleviating PTSD-related nightmares, further research has shown both positive and negative results.

While prazosin is effective in PTSD-related nightmare disorder, it may not be as effective in non-PTSD-related nightmare disorder, and its effects vary from individual to individual.

Other treatments for nightmare disorder

Nightmare disorder, particularly PTSD-related, might not respond uniformly to a single medication. While prazosin is the most studied medicine for PTSD-related nightmares, There are other drugs that have been shown to help nightmare disorder, including:

• Anti-depressants
• Atypical antipsychotics
• Alpha 2 adrenergic antagonists
• Antihistamines/serotonin antagonists
• Sedative hypnotics

Antidepressants

Antidepressants are a type of drug that is used to treat clinical depression.⁵ They work by increasing neurotransmitters such as serotonin and noradrenaline in the brain, which are neurotransmitters linked to mood.⁵ Anti-depressants not only help depression but also can be used for other mental disorders, such as PTSD-related nightmare disorders, such as Trazodone, Mirtazapine, and SSRIS/SSNRIS.⁵

Trazodone

Trazodone, a serotonin antagonist and reuptake inhibitor, is often used to help PTSD-related nightmare disorder.⁶ Evidence shows that trazodone can decrease the frequency of nightmares drastically, though there can be side effects such as low blood pressure.⁶

Mirtazapine

Mirtazapine is an atypical antidepressant which can affect both noradrenergic and serotonergic neurotransmitters.⁷ It can help improve sleep and decrease nightmares.⁷

SSRIs/SNRIs

SSRIS and SNRIS are a type of drug that are considered a main treatment for PTSD; however, their effectiveness in decreasing nightmares is limited.⁸ In some cases, they might even cause nightmares to get worse or increase further.⁸

Atypical antipsychotics

Atypical antipsychotics such as Quetiapine, Olanzapine, and Risperidone are drugs that also work on the serotonin and noradrenaline neurotransmitters and are used to treat psychosis⁹. These drugs should be reserved for cases where the first-line treatments were not effective or if psychotic symptoms are present.

Quetiapine

Quetiapine is bipolar disorder and schizophrenia, but it can be used to treat nightmare disorder, particularly related to PTSD.^9,10 Some studies have shown this can be effective, but there may be side effects such as sedation.^9,10

Olanzapine

Evidence of olanzapine’s use in nightmare disorder is limited, but it has shown effectiveness in some harder-to-treat PTSD patients.¹⁰

Risperidone

Risperidone, given at low doses, has been shown to reduce nightmares in military personnel.^3,6,10 This shows that risperidone may be effective for PTSD-related nightmare disorder.⁶

Alpha-2 adrenergic agonists

Alpha-2 adrenergic agonist drugs such as clonidine suppress the sympathetic nervous system outflow through the brain, therefore decreasing PTSD-related nightmares.⁶

Clonidine

Clonidine, which reduces sympathetic nervous system outflow, has been shown to improve nightmares, specifically in the younger population. However, the scientific evidence of clonidine's effectiveness remains limited.⁶ Clonidine may be considered as a treatment option when prazosin is not tolerated very well.⁶

Serotonin antagonists

Serotonin antagonists are drugs that decrease the neurotransmitter serotonin by blocking their receptors, improving PTSD-related nightmare disorder.⁶

Cyproheptadine

Cyproheptadine is a drug used in the younger population, mostly.⁶ Cyproheptadine has anti-serotonin properties and has been used in reducing nightmares, though evidence on its effectiveness is limited.⁶

Sedatives/Hypnotics

Sedatives are drugs such as benzodiazepines which induce relaxation and decrease anxiety, while hypnotics are sleeping pills that induce sleep, such as z-drugs.¹⁰ These may be effective in managing nightmare disorder, but they are not recommended for long-term use as they do not treat it, but help in the management of symptoms.¹⁰ These drugs also carry a significant risk of dependence and can worsen nightmares when withdrawn from them, so they should be used short-term.¹⁰

Personalised medicine

While all of the drugs mentioned have shown some sort of evidence in the improvement of nightmare disorder, the effectiveness is highly dependent on the individual and the type of nightmare disorder. This is why it is important to tailor treatments based on an individual and their situation, as personalised treatments have been found to be the most effective and with the least side effects. This can be done by taking more than one medicine at a time or taking medicines with other non-pharmacological treatments for nightmare disorder.

Summary

Nightmare disorder is a sleep condition that is characterised by frequent, distressing nightmares and can have a big impact on an individual's daily life and mental health. There are 2 types of nightmares: idiopathic, which are imaginary in nature, and PTSD-related, which are caused by a traumatic event experienced by the individual. Nightmare disorder is often a secondary condition to PTSD, anxiety and depression, making it difficult to diagnose.

If not treated, nightmare disorder can persist for decades. There are many pharmacological treatments that can be used to treat this disorder, with prazosin being the primary one.

Prazosin has been shown to treat nightmare disorder, particularly PTSD-related nightmares, by acting on the noradrenergic and serotonin systems. Though prazosin’s effectiveness varies, and is not suitable for all patients, particularly those with non-PTSD related nightmare disorder.

There are also other pharmacological treatments used to treat nightmare disorder, including: antidepressants, SSRIS/SNRIS, atypical antipsychotics, alpha 2 adrenergic agonists, and sedatives/hypnotics. 

Ultimately, personalised medicine emerges as a key theme in treating nightmare disorder. Tailoring treatments to the individual is important in the effective management of nightmare disorder and its symptoms.