Quviviq versus zopiclone and zolpidem 

Insomnia is one of the most common sleep disorders, affecting millions of people in the UK and worldwide. With so many treatment options available, finding the proper medication can feel overwhelming. In this comprehensive guide, we compare three leading insomnia treatments—Quviviq, Zopiclone, and Zolpidem. We’ll explore how each medication works, their effectiveness, side effects, and which option may be best suited for your unique sleep needs.

You can use the navigational table below to skip to the topics that interest you.

Key takeaways: Quviviq versus Zopiclone and zolpidem

• Different Mechanisms of Action: Quviviq (daridorexant) targets orexin receptors to regulate the sleep-wake cycle, while Zopiclone and Zolpidem are “Z-drugs” that enhance GABA activity to induce sleep more directly.
• Dependence and Tolerance: Quviviq has a lower risk of dependence and tolerance compared to Zopiclone and Zolpidem, which are associated with a higher risk of dependence, particularly with prolonged sleep
• Quality and Architecture: Quviviq is shown to preserve natural sleep architecture better, while Zopiclone and Zolpidem may reduce REM sleep and alter normal sleep patterns.
• Daytime Drowsiness and Cognitive Effects: Quviviq is associated with less next-day drowsiness and cognitive impairment, whereas Zopiclone and Zolpidem can cause morning grogginess and may impact cognitive function, particularly in older adults.
• Best Use Cases: Quviviq is suitable for long-term management of chronic insomnia, while Zopiclone and Zolpidem are typically recommended for short-term use due to their side effect and dependence profiles.
• Buying from online pharmacies: You can purchase Quviviq from online pharmacies but not the Z drugs, such as zopiclone and zolpidem.

What is insomnia?  

Insomnia is a sleep disorder which is responsible for issues with falling and/or staying asleep.

It can cause you to feel tired during the day, which can then affect your concentration levels and lead to a reduced overall quality of life. 

The textbook definition of insomnia is a bit wordy, but here it is:

According to the Diagnostic and Statistical Manual of Mental Disorder, 5^th edition, Text Revision (DSM-5-TR):

Insomnia can be defined as difficulty initiating and/or maintaining sleep, or early-morning awakening despite adequate opportunity for sleep, leading to clinically significant distress or impairments in functioning, and occurring with a frequency of 3 or more nights per week and a duration of 3 months or longer [1]. 

What are the effects of insomnia? 

On top of sleep deprivation, insomnia can lead to many other issues with your daily life, such as but not limited to: 

• Impaired concentration level 
• Reduced  performance at work 
• Increased irritability 

• Daytime exhaustion 
• Difficulties with memory [2]. 

Long-term effects of insomnia

But the consequences of insomnia aren’t just limited to day-to-day alignments; it can also lead to more long-term and severe conditions [3], such as: 

• Depression 
• Increased blood pressure 
• Heart disease 
• An early death 

How insomnia affects your brain

It’s a known fact that a lack of sleep can have implications for your brain function, as you may experience a variety of symptoms, such as: 

• Changes to cognition (see below)
• Changes to your alertness 
• Changes to your attention span 
• Impairments in your decision-making skills 
• Struggling with your memory 

Insomnia and cognition 

Cognition is how your brain converts information that’s taken in into thoughts. There is a strong connection between sleep and cognition.

 Unfortunately, many sleep medications themselves can affect cognition, resulting in poor concentration and memory impairments [4]. 

Hence, a good sleep aid should not only improve sleep quality but also minimise side effects to your natural sleeping patterns as well as your cognition. 

How common is insomnia? 

Insomnia is a condition of high prevalence, affecting around 12-20% of the population [5]. 

Many medications are being used more frequently to help treat insomnia, as in the United States, prescriptions for the treatment of insomnia rose from 5.3 million in 1999 to 20.8 million in 2010 [6]. 

In China, around 339 million sleep pills are used every year, with zolpidem being particularly popular [7]. 

What is Quviviq? 

Quviviq is a revolutionary new drug for treating insomnia.  It belongs to a class of medications known as  DORA  (Dual Orexin Receptor Antagonists).

It is available in two different strengths:

• Quviviq 50mg tablets
• Quviviq 25mg tablets

Unlike other sleeping tablets, which decrease brain activity through the effects of the neurotransmitter GABA, Quviviq (also known as daridorexant) acts on the “switch” in your brain that keeps you awake [8].

When this switch turns off, the signals in your brain that cause you to stay awake are gone, helping you to fall asleep. 

What is a DORA? 

A DORA (Dual Orexin Receptor Antagonist) is a new type of sleep medicine that helps people fall and stay asleep by blocking the orexin receptor [9].

Quviviq (which is just the brand name for the generic drug Daridorexant) is just one compound which belongs to the family of medications known as DORAs. 

What is Orexin?

Orexin is a chemical that is responsible for keeping you awake [9].  

Some animal studies suggest that low doses of DORA can even slightly boost thinking processes. However, there hasn’t been enough clinical evidence at the time of writing this blog to discern the validity of this statement. 

How does Quviviq work? 

Studies have shown that Quviviq not only improves nighttime sleep but also enhances overall daytime performance. 

It works by blocking orexin receptors (OX1R and OX2R) in the brain, which are typically found there to help keep you awake [10].  

Think of the receptors as locks which are only opened by the chemical known as orexin.

When orexin opens these receptors, it triggers the effect of wakefulness. Daridorexant or Quviviq is like a key that sits in a lock but doesn’t open it. So, when Quviviq occupies the OX1R and OX2R receptors, it stops orexin from binding to them.

This means the wakefulness effects of orexin are blocked, making it easier to fall asleep.

How does Quviviq affect sleep? 

A meta-analysis was performed in 2023 to study how different doses of DORA (Dual Orexin Receptor Antagonists) can affect the brain. 

A meta-analysis is when scientists review the results from multiple studies on the same topic and combine them to gain a broader understanding of the topic. Because it pulls together all this information, it’s considered one of the strongest types of evidence in science.

 The meta-analysis found that DORAs, such as Quviviq (also known as daridorexant), didn’t disrupt the structure of sleep.

When compared to a placebo, it had a reported lower frequency of side effects (e.g., headache, lethargy, and fatigue). Patients also reported feeling more awake and refreshed in the morning, and they suffered no severe damage to either daytime function or memory performance [11]. 

The reason this is worth noting is that low doses of zolpidem can help people fall asleep faster and for more extended periods. However, this comes at the cost of impairments and memory during the day after the drug has been taken, which then has implications for the risk of getting into car accidents [11]. 

Quviviq’s implications for memory 

Studies show that orexin can affect the hippocampus, the brain region which has been shown to play a vital role in learning and memory.

This suggests that DORA treatments (e.g., Quviviq), which block orexin, may be capable of improving cognitive and memory problems in individuals with insomnia [12]. 

The  Z drugs, Zopiclone and Zolpidem

Z-drugs are a group of medicines often prescribed to help with sleep problems like insomnia.

The most common Z-drugs are zaleplon (Sonata), zolpidem (Ambien), eszopiclone (Lunesta), and zopiclone.

Z-drugs—like zaleplon (Sonata), zolpidem (Ambien), and eszopiclone (Lunesta)—are common medicines that doctors prescribe to help people with sleep problems, especially insomnia.

Studies show that these medicines can help people fall asleep faster (sleep latency), reducing the time it takes to drift off by approximately 22 minutes compared to a sugar pill (placebo) [13].

These drugs were marketed as being less addictive and causing fewer problems with muscles and memory when compared to some of the older benzodiazepines [14]. However, unfortunately, this didn’t turn out to be the case in reality.

How Benzodiazepines and Z-drugs work:

Benzodiazepines (“benzos”) and Z-drugs are medicines that help people feel calm or sleep better. They both work by affecting special parts of the brain called GABA receptors.

Benzodiazepines: These medicines attach to GABA receptors and make them work better. GABA is a natural chemical in your brain that calms things down. By boosting GABA’s effect, benzos help you feel more relaxed or sleepy [14].

Z-drugs: These medicines also target GABA receptors, but they focus on a specific type linked to sleep (GABA-A receptors). This helps slow down brain activity, making it easier to relax and fall asleep.  Z-drugs are designed to mainly target the sleep areas of the brain rather than those linked to anxiety [15].

The side effects of zopiclone and zolpidem

Although these medicines can be effective, they come with risks. People can become addicted or dependent on them, and stopping suddenly can cause withdrawal symptoms.

Side effects such as drowsiness, dizziness, and difficulty concentrating are also common.

Studies show that using these medicines for a long time—especially in older adults—may lead to memory problems or even increase the risk of dementia  [15].

Because of these risks, doctors usually prescribe Z-drugs (including zopiclone) for only short periods and at the lowest dose that works.

The differences between the Z drugs

Each Z-drug works a little differently [16], [17]:

• Zopiclone and Eszopiclone last longer in the body, so it’s suitable for people who wake up during the night, but it can leave a bad taste in the mouth for some.
• Zaleplon acts quickly but doesn’t last long, so it mainly helps with falling asleep.
• Zolpidem can help with both falling and staying asleep.

Z drugs summary:

Z-drugs, including zopiclone, are helpful for sleep problems but can have side effects and risks, mainly if used for a long time. It’s important to use them carefully and only as directed by a healthcare professional.

Zolpidem

Zolpidem is known to have minor issues when it comes to tolerance and withdrawal symptoms [18].

If you do happen to take zolpidem alongside other drugs that slow down the brain, you could end up suffering from severe breathing difficulties [18]. 

What is Zopiclone?

Zopiclone is a sleep medicine that helps people with insomnia (trouble sleeping). It works by acting on calming receptors in the brain called GABA-A receptors, though it’s not chemically related to older sleep medicines called benzodiazepines. Zopiclone is usually taken as a tablet before bedtime.

How well does it work?

Studies show that zopiclone helps people fall asleep faster, stay asleep longer, and wake up less during the night. It’s effective for both older and younger adults and works just as well as many older sleeping pills. The usual dose for most adults is 7.5 mg, but older adults or those with specific health conditions may start with a lower dose.

Side effects and safety

Zopiclone is generally well tolerated. The most common side effects are a bitter or metallic taste in the mouth and dry mouth. Some people may feel a bit groggy or have trouble with alertness the next morning, but this is usually mild.

Addiction

Due to concerns over the potential abuse and addiction of zopiclone, the GPhC, the governing body for pharmacy in the UK, decided that Z drugs, such as zopiclone, could not be purchased online [20].

Which is better, Quviviq or the Z drugs? 

Simply put, our answer in this blog is Quviviq.  

The reason is simple: it helps to cure insomnia by letting you fall asleep comfortably without compromising your thinking ability the day after, whereas zopiclone and zolpidem are both very effective at keeping you asleep but at the cost of more side effects, which can alter your memory processes.  

 Comparison Table: Quviviq vs Zopiclone vs Zolpidem

Feature	Quviviq (Daridorexant)	Zopiclone	Zolpidem
Class	Dual orexin receptor antagonist	Z-drug (non-benzodiazepine)	Z-drug (non-benzodiazepine)
How it Works	Blocks orexin (wake-promoting) signals to aid sleep	Enhances GABA activity to promote sleep	Enhances GABA activity to encourage sleep
Onset of Action	30 minutes to 2 hours	30-60 minutes	15-30 minutes
Duration	7-8 hours	6-8 hours	6-8 hours (IR), up to 8 (CR)
Effect on Sleep Stages	Preserves natural sleep architecture	It may reduce REM sleep	It may reduce REM sleep
Daytime Drowsiness	Low risk	Moderate risk	Moderate risk
Dependence & Tolerance	Low risk	Higher risk	Higher risk
Withdrawal Symptoms	Uncommon	Possible	Possible
Cognitive Impairment	Minimal	Possible, especially in the elderly	Possible, especially in the elderly
Approved Use	Chronic insomnia	Short-term insomnia	Short-term insomnia
Common Side Effects	Headache, fatigue, somnolence	Bitter taste, dry mouth, drowsiness	Dizziness, headache, drowsiness
Controlled Substance?	Yes (Schedule IV, UK)	Yes (Schedule IV, UK)	Yes (Schedule IV, UK)
Notable Pros	A lower risk of dependence preserves sleep quality, making it suitable for long-term use.	Rapid onset, effective for short-term use	Rapid onset, effective for sleep initiation
Notable Cons	Newer drugs (less long-term data) may be more expensive	Dependence risk, morning grogginess, metallic taste	Dependence risk, potential for sleepwalking or memory issues

Feature	Quviviq (Daridorexant)	Zopiclone	Zolpidem
Class	Dual orexin receptor antagonist	Z-drug (non-benzodiazepine)	Z-drug (non-benzodiazepine)
How it Works	Blocks orexin (wake-promoting) signals to aid sleep	Enhances GABA activity to promote sleep	Enhances GABA activity to encourage sleep
Onset of Action	30 minutes to 2 hours	30-60 minutes	15-30 minutes
Duration	7-8 hours	6-8 hours	6-8 hours (IR), up to 8 (CR)
Effect on Sleep Stages	Preserves natural sleep architecture	It may reduce REM sleep	It may reduce REM sleep
Daytime Drowsiness	Low risk	Moderate risk	Moderate risk
Dependence & Tolerance	Low risk	Higher risk	Higher risk
Withdrawal Symptoms	Uncommon	Possible	Possible
Cognitive Impairment	Minimal	Possible, especially in the elderly	Possible, especially in the elderly
Approved Use	Chronic insomnia	Short-term insomnia	Short-term insomnia
Common Side Effects	Headache, fatigue, somnolence	Bitter taste, dry mouth, drowsiness	Dizziness, headache, drowsiness
Controlled Substance?	Yes (Schedule IV, UK)	Yes (Schedule IV, UK)	Yes (Schedule IV, UK)
Notable Pros	A lower risk of dependence preserves sleep quality, making it suitable for long-term use.	Rapid onset, effective for short-term use	Rapid onset, effective for sleep initiation
Notable Cons	Newer drugs (less long-term data) may be more expensive	Dependence risk, morning grogginess, metallic taste	Dependence risk, potential for sleepwalking or memory issues

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Summary

Quviviq (daridorexant), Zopiclone, and Zolpidem are all used to treat insomnia, but they differ in their mechanisms, risks, and recommended uses.

Quviviq is a newer medication that targets orexin receptors, helping to regulate the sleep-wake cycle with a lower risk of dependence and less disruption to natural sleep patterns. This makes it a promising option for long-term insomnia management.

Zopiclone and Zolpidem are both Z-drugs that act on GABA receptors to induce sleep rapidly. They are effective for short-term use but come with higher risks of dependence, tolerance, and next-day drowsiness. Both can alter sleep architecture, particularly by reducing REM sleep and may cause cognitive impairment, especially in older adults.

For those seeking a sustainable, long-term solution with fewer risks, Quviviq may be a preferable option.

However, for immediate, short-term relief, Zopiclone and Zolpidem remain widely prescribed. Always consult a healthcare professional before starting or switching insomnia medications.

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Which is better, Quviviq or the Z drugs? 

Simply put, our answer in this blog is Quviviq.  

The reason is simple: it helps to cure insomnia by letting you fall asleep comfortably without compromising your thinking ability the day after, whereas zopiclone and zolpidem are both very effective at keeping you asleep but at the cost of more side effects, which can alter your memory processes.  

FAQs

Can you buy zopiclone online?

No, due to new guidance by the General Pharmaceutical Council, the Z drugs such as zopiclone cannot be purchased online due to their potential for abuse and addiction.

Can you buy Quviviq online?

Yes, you can purchase Quviviq 50mg and Quviviq 25mg after completing an online consultation.

Is Quviviq addictive?

No, Quviviq is not addictive, which is why it is licensed for chronic insomnia.

How does Quviviq work?

Quviviq works by blocking the OX1R and OX2R receptors, which stops the binding of orexin. It turns off the area of the brain that keeps us awake.

How long does Quviviq last for?

Quviviq will last for around 8 hours.

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