Phases of SSRI Withdrawal

If you or a loved one is going through SSRI withdrawal, then knowing the phases is important. Keep reading to learn more about the phases of SSRI withdrawal and what to expect. 

Table of Contents

What is SSRI?

One of the most important aspects of helping a loved one with any issue is knowledge. Being able to handle a problem from any angle with compassion and information is critical. It helps your loved one feel heard and cared for. As such, understanding the phases of SSRI withdrawal is essential for recovery.1

SSRI stands for selective serotonin reuptake inhibitor. SSRIs are the most commonly prescribed type of antidepressant. They ease the symptoms of moderate to severe depression. They are considered to be relatively safe, and they tend to cause fewer side effects than other types of antidepressants. 

How Do SSRIs Work?

SSRIs are used to treat depression. When the substance enters the body, it increases the amount of serotonin in the brain. Serotonin is a neurotransmitter in the brain. Neurotransmitters are the chemical messengers in our bodies. They carry messages between the brain nerve cells. These messages are also referred to as signals.

Serotonin is known as the happy chemical. It contributes to happiness and well-being, as well as other matters in the body. As such, increasing the amount of serotonin in the brain can make a person happier and alleviate depression.2

SSRIs are inhibitors. They specifically work by blocking the reabsorption (reuptake) of serotonin into neurons, meaning that there is more serotonin available, increasing its transmission between neurons. The name includes the term “selective” because these medications only affect (select) serotonin. 

How Long Do They Take to Work?

When using SSRIs, the effects are not felt immediately. It takes time for the medication to take effect. Some users experience the desired effect within two to four weeks, while others take up to six weeks to feel anything. As such, the effects of the medication should be felt within eight weeks. If there are no changes in feeling or mood after that period a medical professional should be consulted. 

How Long Do They Stay in the System?

SSRIs stay in your system for a varied amount of time-based on the specific medication being taken. Most of the commonly prescribed SSRIs are half out of the body within forty-eight hours and have fully left the body within a week. However, some take six days to reach the point where half of the substance is out of the body, and up to a month to leave the body completely. It depends entirely on the SSRI in question. 

Types of SSRIs

For the most part, SSRIs are used to treat mental health conditions. There are three main uses for SSRIs.


As discussed previously, SSRIs are used to treat depression by increasing the amount of serotonin in the brain. They help people feel generally happier since serotonin is responsible for feeling happy feelings. More serotonin means an easier time transmitting “happy” signals to neurons in the brain. 


SSRIs have been used to help treat anxiety as well. They reduce the “volume” of anxious thoughts, meaning that anxiety is felt less intensely. Physical symptoms of anxiety also tend to be reduced, including muscle tension and interruptions in sleep cycles. 

Mood Disorders

For individuals who suffer from mood disorders, a mood stabilizer on its own is not effective. SSRIs can be prescribed alongside them to make medication more effective. They allow the brain to be more receptive to the effects of the stabilizer by increasing serotonin levels. This method of treatment has to be monitored heavily by the treating physician, however. 

Half-Lives of Common SSRI Medications

Below you will find a list of common SSRI medications, what they are used for, and what their half-lives are. The half-life of a medication describes how much time it takes for half of the substance to leave the body. It depends on how the body processes the medication, and how it gets rid of the substance. Some medications take longer to leave the body than others due to these variables. 


Prozac is an SSRI medication used for the treatment of depression, primarily. It has also been used for obsessive compulsive disorder and bulimia in certain cases. It typically has fewer side effects than other antidepressants, making it commonly prescribed. It takes four to six weeks for the medication to be felt. Its half-life is anywhere from one to four days depending on the metabolic rate of the individual taking the medication.


Celexa is another SSRI medication used to treat depression. It is known for improving energy levels and feelings of well-being. The medication also takes approximately four to six weeks to be felt by individuals taking it. Celexa’s half-life is one and a half to two days in most cases, meaning that its half-life is very fast for most patients.


Unlike the other antidepressants on this list, Lexapro is for use by patients who have major depressive disorder, rather than moderate depression. It is also used for generalized anxiety disorder. Lexapro is known for working within four to six weeks, with six weeks being more common for users. Its half-life is one to one and a half days, meaning that it exits the body rapidly.


Paxil has been used in a wide number of applications in the medical field. It is used for treatment for depression, panic attacks, obsessive compulsive disorder, anxiety disorders, and post-traumatic stress disorder. Full benefits from Paxil can be felt within six weeks. The medication has a half-life of twenty-four hours.


Zoloft is an SSRI medication that is prescribed to both children and adults. It has been approved for the treatment of major depressive disorder, post-traumatic stress disorder, panic disorder, social anxiety disorder, and obsessive compulsive disorder. Zoloft has been shown to work within the first one to two weeks of use. The half-life for Zoloft is anywhere from one to one and a half days.

Common Side Effects of SSRI Medication

The majority of SSRI medications have been shown to work in the same way, and have similar side effects. Some people experience many of the side effects listed below, and some feel no side effects whatsoever. Take a look at the possible side effects of SSRI medications below.

Physical Side Effects

These are the most common physical side effects of SSRI medications:

  • Feeling or being sick
  • Indigestion, constipation, or diarrhea
  • Loss of appetite followed by weight loss
  • Dizziness
  • Blurred vision
  • Dry mouth
  • Excessive sweating
  • Issues with sleep cycles, like insomnia 

Mental Side Effects

In addition to physical side effects, several mental side effects can occur when taking SSRI medications:

  • Low sex drive
  • Headaches
  • Confusion
  • Hallucinations 

Drug Interactions

SSRI medications can have interactions with other drugs as well. Some of the medications that SSRIs can interact with are listed below.

  • Non-steroidal anti-inflammatory drugs like ibuprofen and naproxen
  • Antiplatelets used to prevent blood clots
  • Theophylline, an asthma medication
  • Clozapine and Pimozide, two medications used for treating schizophrenia and psychosis
  • Lithium, a medication used for treating bipolar disorder
  • Triptans, a group of medications used to treat migraines
  • Other antidepressants

When SSRI medications interact with these drugs they increase the likelihood of bleeding issues. They can also cause “serotonin syndrome,” which is when the body has too much serotonin in it. It can lead to a plethora of side effects as well, including dangerous symptoms and extreme nerve cell activity.

It is always important to consult with your doctor about any and all medications that you are taking when SSRI medications come up. They can interact unpredictably with prescription drugs and over-the-counter medications in life-threatening ways.9  

SSRI Discontinuation Syndrome

SSRI discontinuation syndrome, also known as antidepressant discontinuation symptom, occurs in about 20% of patients who abruptly stop taking their SSRI medications. It is most common when the medication in question was taken for at least six weeks. Several different symptoms can occur when an individual experiences SSRI discontinuation syndrome.10 

Sensory Symptoms

Some of the most confusing symptoms of SSRI discontinuation syndrome are the associated sensory symptoms. Some individuals report a feeling of burning in their appendages, also known as paresthesia. Others state that they experience numbness in their extremities. Other sensory symptoms include electric-shock sensations, rushing noises in the head, and visual trails. 


Individuals suffering from SSRI discontinuation syndrome may experience disequilibrium in several ways, as well. The most commonly reported symptoms associated with this are light-headedness, vertigo, and dizzy spells. 

General Somatic Symptoms

A lot of the time these issues are referred to as flu-like symptoms. Many of the symptoms of the flu are comparable in severity, such as lethargy and fatigue, headaches, tremors, and sweating. For the individual suffering from the syndrome, they may be convinced that they have the flu. It can also cause stomach disturbances and a loss of appetite, causing anorexic habits to avoid the unpleasantness that follows eating. 

Affective Symptoms

Affective symptoms refer to a person’s mood and demeanor. As such, these are mood-altering symptoms. The syndrome can cause individuals to experience high levels of irritability. It can also cause increased symptoms of anxiety, leading to agitation. They may also display a low mood, associated with a depressive state. Tearful states are common, and crying for what seems like no reason is not out of the ordinary. Remember that what they are feeling is real, though, and difficult to handle. 

Gastrointestinal Symptoms

Gastrointestinal symptoms may occur without the accompaniment of other flu-like symptoms. Individuals often experience strong nausea. This nausea can lead to bouts of vomiting. Diarrhea may be a symptom that occurs as well. 

Sleep Disturbance

Sleep disturbances can refer to a large number of symptoms. Most of the time, insomnia is encountered. This difficulty with sleeping can lead to some of the other effective symptoms listed above. In addition to insomnia, however, more intense symptoms may be experienced. Many patients report having vivid nightmares, or excessive dreaming. Both of these can play a large part in the mental health of the individual suffering from SSRI discontinuation syndrome. 

Looking for Discontinuation Symptoms Using the FINISH Method

Should you expect a loved one has abruptly ended the use of their SSRI medication, there is a mnemonic device that allows you to look for the symptoms easily. The mnemonic device is FINISH, and each letter helps to describe the symptoms that you should be looking for in a simpler way than remembering the above terms.11 


It’s important to understand when these symptoms are experienced, and how long they will last. Often, the onset of symptoms is related to the half-life of the SSRI medication in question. As such, withdrawal symptoms may be experienced as soon as one to three days after ending medication abruptly. Then, the symptoms may be present for a significant amount of time. Some SSRI medications leave the body almost completely within one week. Others take three weeks to a month. Even after the medication has left the body entirely, symptoms may persist.12 

F: Flu-Like Symptoms

Look for any symptoms that may seem related to the flu, which can include several different symptoms. Headaches are common. So are cold sweats and tremors. They may be experiencing appetite loss and lethargy. Nearly all symptoms of the flu can be associated with SSRI discontinuation syndrome as well. 

I: Insomnia

While insomnia is not the only disturbance to the sleep cycle that can be experienced, it is the most common. It is also the most easily identifiable. Should sleeping be difficult for an individual suspected of abruptly stopping their medication, they may be experiencing withdrawal. 

N: Nausea

Nausea is often the precursor to the other gastrointestinal issues caused by SSRI discontinuation syndrome. It leads to vomiting when experienced intensely, and can also be an indicator of unpleasant bowel movements. Nausea can also lead to a loss of appetite, which causes noticeable weight loss. 

I: Imbalance

This issue is much easier to remember than disequilibrium. Imbalance can refer to the general dizziness caused by withdrawal, as well as light-headed experiences and vertigo. 

S: Sensory Disturbances

Sensory disturbances are some of the more alarming symptoms associated with SSRI discontinuation syndrome. It can manifest as a burning sensation in the appendages, or as the feeling of being shocked consistently. In other cases, blurred vision with visual trails appears, as well as rushing noises in the head. 

H: Hyperarousal

A more uncommon term, hyperarousal can relate to some things listed above. It may be related to the inability to sleep. It can also refer to the affective symptoms of SSRI discontinuation syndrome, like irritability or agitation. It is a symptom commonly seen in individuals experiencing post-traumatic stress disorder. 

Prevention of SSRI Withdrawal Syndrome

When ending the use of SSRI medications, it is important to take the right precautions to avoid SSRI withdrawal syndrome. 

Gradual Weaning

Similar to many other medications, SSRI medications should be gradually weaned off, which is also referred to as “tapering.” Dose reductions can be taken to help reduce the likelihood of withdrawal from SSRI medications. The doses are normally reduced in intervals, though is unlikely that the reduction will be fast, however.

When tapering off depression meds, the right amount of time must be taken to prevent withdrawal. Dosage reductions can happen as quickly as two-week intervals, meaning that every two weeks the dosage of the SSRI medication would be reduced. However, depending on how long the medication has been taken, and the strength of the initial dose, reductions may take as long as six weeks.

Should solid dose adjustments create too large a gap in dosage strength, liquid doses may be given in addition to solid doses. This aspect helps the tapering process as the strength can be fine-tuned to prevent any ill side effects from being experienced. 

Professional Guidelines

As with any medication that’s being tapered, speak with a professional and receive a treatment plan. Some professional guidelines assist a physician in creating a dosage reduction plan for tapering. They can include the amount of the dose currently being administered, how long the medication has been taken, and any past symptoms experienced while taking the medication.

Generally speaking, professional guidelines recommend dosage reductions happening in short-term intervals. The most common time frame for a reduction is two to four weeks. The dose gradually decreases until the goal dose is reached, usually a therapeutic minimum dose. Then it is lowered to minimum half-doses until complete cessation is achieved. 

Key Takeaways

SSRI medications are selective antidepressants that focus on increasing serotonin in the body. They are used to treat depression, anxiety, and other mental health disorders. While they are generally considered safe, there are still precautions that must be taken when prescribed them. Abruptly stopping an SSRI medication can lead to severe withdrawal symptoms that affect daily life. As such, there are key things to look for if withdrawal is suspected, using the mnemonic device FINISH. Tapering is the best method for ending SSRI medication use, and it should be planned by a medical professional to ensure that it is done correctly.  


If you or a loved one needs help, please call us at
623-523-4748 and our team at Blueprints For Recovery in Arizona will help.

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