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Phenibut Withdrawal Timeline

Medically Reviewed By: Benjamin Caleb Williams RN, BA, CEN

Written By: Phillippe Greenough

Article Updated: 01/25/2021

Number of References: 19 Sources

Phenibut has been increasing in popularity in recent years and, contrary to popular belief, is capable of producing dependence, addiction, and withdrawal symptoms. The symptoms of phenibut withdrawal can be very uncomfortable and include seizures, psychosis, insomnia, and delirium. These symptoms may last for around a week or two and may even be dangerous in some cases. Here, we will look at the way this drug works, the phenibut withdrawal symptoms, the timeline involved, and when a phenibut detox center may be particularly beneficial.

In This Article:

Phenibut Withdrawal Symptoms

The timeline for the symptoms of phenibut withdrawal can vary quite a lot between individuals. This has to do with someone’s unique genetics, their phenibut use habits, co-occurring mental health issues, and liver function. While the total timeline may vary, the progression of phenibut withdrawal symptoms is fairly standard and roughly mirrors the withdrawal syndrome and progression from benzodiazepines. Phenibut has a fairly short half-life of around 5 hours in a healthy adult, so someone will begin to experience withdrawal symptoms within 10 hours of the last phenibut use. Symptoms may begin mildly and then escalate over the first few days before stabilizing and then slowly resolving. The acute phase is roughly a week-long and will transition into the post-acute phase, the duration of which shows substantial variability between individuals.

The symptoms of phenibut withdrawal can be thought of as opposites of the effects produced by using the drug. While phenibut use produces relaxation, anti-anxiety effects, euphoria, and anticonvulsant properties, withdrawal from phenibut produces hyperactive neurological and psychological symptoms. These symptoms can range from simply uncomfortable, to potentially life-threatening depending on someone’s phenibut use habits and several other factors. Additionally, physiological dependence on phenibut can develop fairly quickly; sometimes within days to weeks of consistent use. This means that after using phenibut for just a few weeks, someone may experience fairly severe withdrawal symptoms once they quit using the drug.

If left untreated, the symptoms of phenibut withdrawal may lead to potentially dangerous or fatal outcomes. In the case of delirium, psychosis, and hallucinations this is especially so, as someone may hurt themselves or others without realizing it. When these symptoms are coupled with increased irritability and aggression, it is possible that someone may hurt others intentionally, even if they are normally non-violent and peaceful people. These risks of directed harm are very serious, and that is not even mentioning the increased risk of seizures during phenibut withdrawal. A seizure can easily result in dangerous complications, such as direct neurological complications or due to injuries sustained secondary to the seizure. Phenibut withdrawal poses a variety of risks to someone’s health and life, and entering a phenibut detox center is highly recommended if someone is expecting to undergo phenibut withdrawal.

While phenibut withdrawal has not been well studied, a broad generalization of the phenibut withdrawal timeline may look something like this:

Week 1

Within hours of the last phenibut use, withdrawal symptoms will begin to emerge. The first symptoms are usually increased sweating, anxiety, and shaking. By the end of the first day, these symptoms will have intensified and will often be joined by irritability, muscle pains, mood swings, and confusion. Insomnia often appears the first night of withdrawal, and the next few days will exhibit and intensification of these symptoms. Around the middle of the first week, hallucinations, delirium, and the risk of seizures are the most prevalent. These three symptoms usually resolve towards the end of the week, but the rest of the less directly dangerous symptoms often remain at fairly intense levels.

Some of the symptoms of phenibut withdrawal that may be expected during the first week can include:

  • Intense Anxiety
  • Deep Depression (with or without suicidal ideation)
  • Anhedonia (reduced ability to experience pleasure)
  • Mood Swings
  • Intense Cravings for Phenibut
  • Tremor or Shaking
  • Myoclonus (muscle spasms)
  • Diaphoresis (constant sweating)
  • Nausea and Vomiting
  • Stomach and Muscle Pain
  • Increased Irritability or Aggression
  • Psychosis
  • Confusion and Delirium
  • Hallucinations (visual, auditory, tactile, or a combination)
  • Seizures
  • Tachycardia (increased heart rate)
  • Hypertension (elevated blood pressure)
  • Hyperthermia (elevated body temperature or fever)
  • Hyperreflexia (exaggerated reflexes)
  • Insomnia
  • Cognitive Deficits (problems with memory and reasoning)

Week 2

The beginning of the second week may start off quite rough, as the acute withdrawal symptoms are still fairly close to their peak intensity. As the days pass, however, the physical symptoms typically resolve substantially, with an almost complete remission by mid-week. The psychological symptoms, on the other hand, have usually shown little improvement during the second week, and often leave the week at about the same severity as they entered it. The psychological symptoms may seem more intense by the end of the week, but this is usually due to the fact that as the physical symptoms resolve, they are no longer present to distract from the psychological symptoms, thus making them seem more intense.

Some symptoms of phenibut withdrawal that may persist into the second week may include:

  • Intense Anxiety
  • Deep Depression (with or without suicidal ideation)
  • Anhedonia (reduced ability to experience pleasure)
  • Mood Swings
  • Strong Cravings for Phenibut
  • Tremors or Shaking
  • Nausea
  • Stomach Pain
  • Increased Irritability
  • Insomnia
  • Cognitive Deficits (problems with memory and reasoning)

Weeks 3 & 4

By the third week, insomnia may begin to resolve and the psychological symptoms may see some improvement as the week progresses. Getting more sleep each night will help the body and brain recover from the often traumatic first week of phenibut withdrawal symptoms, although it will still take some time for someone to feel somewhat normal again. The fourth week often shows the first signs of hope for someone undergoing phenibut withdrawal. The physical symptoms are often fully resolved at this point and the psychological symptoms may have shown a good deal of improvement. That being said, the challenges are not over as relapses tend to occur during or shortly after withdrawal has concluded.

Some symptoms of phenibut withdrawal that may last into the third or fourth weeks of withdrawal may include:

  • Anxiety
  • Deep Depression (with or without suicidal ideation)
  • Anhedonia (reduced ability to experience pleasure)
  • Mood Swings
  • Cravings for Phenibut
  • Irritability
  • Minor Insomnia
  • Cognitive Deficits (problems with memory and reasoning)

Post-Acute Withdrawal Symptoms

The post-acute phase of phenibut withdrawal can be much longer-lasting than the acute, or immediate phase, although the symptoms are usually much less intense. While they rarely pose a direct physical danger to someone’s health, there are secondary complications that may arise.

Some of the symptoms of post-acute withdrawal from phenibut include:

  • Depression (with or without suicidal ideation)
  • Anxiety
  • Mood Swings
  • Fatigue and Lethargy
  • Cravings for Phenibut
  • Insomnia

These symptoms can persist for weeks, months, and sometimes even years after phenibut use ceases. Depression is of particular note, as the risk of suicidal thoughts, or even suicide attempts are a real danger during post-acute withdrawal. These symptoms will fully resolve with continued abstinence from phenibut, but medications and therapy may be able to help reduce their intensity while neurological recovery occurs.

More About Phenibut Addiction

Phenibut is a member of the gabapentinoid family which is a group of drugs that are structurally similar, or analogs of the neurotransmitter GABA. This class of drugs exhibits inhibitory neurological effects that may include anticonvulsive, anti-anxiety, and euphoric properties. Originally developed in the USSR in the 1960s, phenibut is an anti-anxiety medication that also produces mild cognition-enhancing, or nootropic, effects. Commonly marketed in the US as a “nutritional supplement” this drug is proving to be very dangerous, especially when the risks and dangers of using it are not made clear. When prescribed by a doctor in countries like Russia, the risks and benefits may be properly weighed, but when it is abused, it can produce very uncomfortable and potentially deadly withdrawal symptoms.

The way phenibut works is very broadly similar to more commonly abused GABA agents such as gabapentin or pregabalin. While the exact mechanism of action is different from these more common drugs, the end result is somewhat similar. Phenibut works indirectly as a GABA-B and to a lesser degree GABA-A neurotransmitter agonist, or stimulator, through its primary action on α2δ calcium channel receptor subunits. Through interaction with these subunits, GABA signaling is intensified, thereby producing a calming effect throughout the brain. Phenibut also increases dopamine signaling in the brain, although the exact way this happens is unclear. This complex mechanism of action is responsible for phenibut being used as both an anti-anxiety medication and a nootropic drug, as it can calm some processes while speeding up others.

Through chronic and heavy phenibut use, the brain will begin to make changes in an attempt to maintain balance. Due to the increased levels of the neurotransmitter GABA produced through phenibut use, the brain will perform a process known as “downregulation” to GABA receptors that essentially turns down their sensitivity to GABA. If phenibut use continues, so will GABA downregulation which will, over time, build a tolerance to phenibut, and someone will require larger amounts of the drug to produce the same effect. Another change made by the brain is known as neurological remodeling, and this begins shortly after downregulation although it takes some time to produce noticeable effects. Remodeling is a process of structural changes made by the brain in response to downregulation. Other changes made in the brain due to phenibut use include downregulation to dopamine receptors and remodeling to dopamine systems, particularly in the limbic system. Once downregulation and remodeling have occurred, someone will begin to experience symptoms of phenibut withdrawal when they go too long without using the drug.

The Importance of Detox

Phenibut withdrawal and detox can introduce and increase a wide range of risks to someone’s health and life. The risk of seizure, suicidal ideation, and harm to others can be greatly increased during this time, and depending on certain factors, these risks may be increased even more. Here are some of the situations that may indicate a phenibut detox center is especially important:

Phenibut addiction can be devastating to someone’s life, state of mind, and chances of happiness. While it may not seem like it at times, recovery is possible. It will take work and sustained effort, but with help, it can be a reality. All that it requires is the courage to reach out and ask for help and the willingness to receive that help. Don’t wait, recovery is possible and it can start today.

Related Guides

There are several other depressant drugs that can produce uncomfortable or even dangerous withdrawal symptoms. We have more in-depth withdrawal guides for drugs such as:

Marijuana Withdrawal Timeline

Gabapentin Withdrawal Timeline

Lyrica Withdrawal Timeline

GHB Withdrawal Timeline

Spice Withdrawal Timeline

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