Disclaimer:
This article is for educational purposes only. It is not medical advice, and individual experiences with Lexapro vary significantly from person to person. Always consult your medical provider before starting or stopping any medication. If you are experiencing severe side effects, worsening mood, or thoughts of harming yourself, seek immediate medical help or go to the emergency room.
As therapists who works closely with clients navigating anxiety and depression, including many in the Palm Beach Gardens and Jupiter community, we are frequently asked about what to expect during the first week on Lexapro (escitalopram). Whether you are starting treatment for the first time or switching from another antidepressant, the first several days can bring a mix of physical and emotional reactions. Understanding what’s typical can help you feel more grounded and prepared.
In this guide, we’ll break down the most common Lexapro side effects in the first week, dosage expectations, emotional responses, and the signs that indicate you should call your doctor. This is a comprehensive resource for anyone wanting clarity and reassurance during the adjustment period.
What is Lexapro?
Lexapro, also known by its generic name escitalopram oxalate, is a prescription medication commonly used to treat:
- Anxiety disorders
- Major depressive disorder
- Certain panic or stress-related conditions
- Mood disturbances associated with serotonin imbalance
If you’ve ever wondered what Lexapro is, it is one of the most widely prescribed selective serotonin reuptake inhibitors (SSRIs) in the United States. Many people find it effective and well-tolerated, though the first week may come with noticeable changes.
Overview of Escitalopram
Escitalopram is part of a class of antidepressants known as SSRIs. If you’ve asked yourself, “Is Lexapro an SSRI?” the answer is yes—one of the most researched ones.
SSRIs work by increasing serotonin levels in the brain. Serotonin is associated with mood stability, emotional resilience, and feelings of well-being.
You may see escitalopram labeled in different forms, including:
- Escitalopram 10 mg
- Escitalopram 20 mg
- Lexapro generic or store-brand equivalents
The medication is considered both effective and relatively gentle, though side effects—much like any antidepressant—are possible, especially during the first week.
What Does Lexapro Do?
To understand what does Lexapro do, think of serotonin like the brain’s “emotional shock absorbers.” When serotonin levels are low or dysregulated, people may experience depression, anxiety, irritability, panic, or emotional overwhelm.
Lexapro helps by:
- Boosting serotonin availability
- Supporting emotional balance
- Reducing symptoms of anxiety
- Improving mood regulation
- Supporting healthier thought patterns over time
Clients often describe Lexapro as something that “turns down the intensity” of anxious thoughts rather than eliminating them entirely.
How Does Lexapro Work?
Lexapro works gradually, not instantly. Many people mistakenly assume medications like Lexapro will make them feel significantly better within a day or two. In reality:
- The first week may bring side effects.
- Emotional changes typically appear between 2–6 weeks.
- Full therapeutic effects may take 6–12 weeks, especially for anxiety.
Lexapro works by blocking serotonin reuptake so more serotonin remains available in the brain. This subtle change gradually shifts mood, sleep, energy, and stress response.
What Does Lexapro Feel Like When It Starts to Work?
This is one of the most common questions we hear from patients, and it makes sense—when you're anxious or depressed, you want to know what "better" is actually going to feel like.
Unlike the first-week side effects, which tend to show up fast and fade, the feeling of Lexapro "working" is usually gradual and subtle rather than dramatic. Most people don't wake up one day feeling like a different person. Instead, they notice small shifts that build over time.
Common ways clients describe it include:
- A quieter baseline. Anxious thoughts don't disappear, but they stop feeling as loud or urgent.
- More space between a trigger and a reaction. Stressful moments still happen, but they don't spiral as quickly.
- Feeling more "even." Fewer extreme highs and lows; moods feel more level day to day.
- Improved resilience. Setbacks that used to derail an entire day become easier to move past.
- Better sleep and appetite regulation once the initial adjustment period passes.
- A gradual lifting of the mental fog that can come with depression or chronic anxiety.
It's also common for people to not notice the change themselves; friends, partners, or family members often point it out first, since gradual shifts can be hard to see from the inside.
If you're a few weeks in and wondering whether it's "working," a helpful exercise is to compare how you're doing now to how you were doing on day one, rather than comparing today to yesterday. Progress on SSRIs is usually easier to see in hindsight than in the moment.
As always, if you feel like the medication isn't working after an adequate trial period (typically 6-8 weeks at a therapeutic dose), that's worth discussing with your prescribing provider—it may mean a dose adjustment or a different medication is a better fit.
Lexapro Dosage Options
Your provider may start you on a low dose to minimize Lexapro side effects in the first week and increase gradually if needed.
The most common dosing includes:
Escitalopram 5 mg
While 10 mg is the more commonly cited starting dose, many providers begin patients—especially those who are highly sensitive to medication, older adults, or people prone to anxiety around new side effects—on escitalopram 5 mg instead.
The idea behind a 5 mg starting dose is simple: give the body a smaller initial adjustment so that side effects are gentler, then increase the dose after a week or two if needed and well tolerated.
What tends to be different about the first week on 5 mg compared to 10 mg or 20 mg:
- Milder side effects overall. Fatigue, GI upset, and sleep disruption are still possible, but often less intense.
- Slower symptom relief. Because the dose is lower, therapeutic benefits for anxiety or depression may take a bit longer to become noticeable.
- Still requires the same patience. Even at a lower dose, meaningful therapeutic effects generally aren't expected until several weeks in.
- A common "step-up" dose. Many providers use 5 mg as a short-term starting point before moving to 10 mg, rather than a long-term maintenance dose.
If you've been started on 5 mg, it doesn't mean your symptoms are less serious—it usually reflects a more cautious titration approach. Any changes to your dose should be made in conversation with your prescribing provider, not on your own.
Escitalopram 10 mg
This is the standard starting dose for many adults. It is strong enough to begin impacting serotonin levels but gentle enough to limit severe side effects.
A doctor may increase to 20 mg depending on symptom severity.
Escitalopram 20 mg
This is often used for:
- Moderate to severe anxiety
- Major depression
- When 10 mg is helpful but not sufficient
An increase is usually only recommended after several weeks. You would need to discuss your proper dosage and any dosage changes with your prescribing physician
Lexapro Generic Variants
Pharmacies may dispense:
- Escitalopram tablets
- Brand-name Lexapro
- Generic escitalopram oxalate
Generics are widely used and considered equivalent.
Common Side Effects in the First Week
When starting Lexapro, the first week is often when the body adjusts to new serotonin levels. Many people experience mild to moderate side effects that usually improve within 7–14 days.
Below are the most common Lexapro side effects experienced in the first week and what they feel like.
Fatigue and Exhaustion
One of the top searches is can Lexapro make you tired? and the answer is: yes, it often can—especially during the first week.
Fatigue-related symptoms include:
- Feeling unusually sleepy
- Needing naps
- Low motivation
- “Lexapro exhaustion”
- Feeling mentally foggy
- Extreme fatigue during the first several days
These symptoms are typically temporary. Staying hydrated and maintaining consistent sleep schedules can help.
Insomnia and Sleeplessness
Surprisingly, Lexapro can also have the opposite effect. Many people wonder:
- Can Lexapro cause insomnia?
- Will Lexapro cause sleeplessness?
- Can Lexapro cause sleeplessness?
Yes, sleeplessness is extremely common in the first week.
Symptoms may include:
- Difficulty falling asleep
- Waking up frequently
- Early morning awakenings
- Light, restless sleep
- Racing thoughts at night (paradoxically increased anxiety early on)
These effects typically settle after 1–2 weeks.
Constipation and Digestive Issues
Digestive reactions are common when adjusting to SSRIs. Many people ask:
- Does Lexapro cause constipation?
- Does Lexapro make you constipated?
Yes, Lexapro can slow digestion temporarily.
Common GI side effects include:
- Mild constipation
- Bloating
- Delayed bowel movements
- Nausea
- Mild stomach discomfort
Hydration, fiber, and movement can support more comfortable digestion.
Emotional Side Effects
The emotional experience during the first week can vary widely.
Some people experience:
- Emotional blunting
- Temporary irritability
- Heightened anxiety
- Lightheadedness
- Feeling “off” or “disconnected”
- Mood swings
- Increased sensitivity to stress
These reactions can feel alarming but are typically temporary. Many people feel more “even” after the first two weeks.
Lexapro and Anxiety
A major reason people begin Lexapro is anxiety. Yet in the first week, Lexapro for anxiety can paradoxically increase anxiety—this is well-documented and normal.
Why does this happen?
As serotonin levels shift, the body temporarily becomes more sensitive to internal sensations. This can create an uptick in symptoms like:
- Rapid heartbeat
- Rumination
- Restlessness
- Feeling panicky or overstimulated
If you’re wondering, does Lexapro help with anxiety?—yes, but the benefits usually come after the adjustment period, not during the first week.
Many clients in our practice (including those who see a therapist Palm Beach Gardens area for anxiety treatment) report that weeks 2–4 bring noticeable calm, improved emotional regulation, and better sleep.
Lexapro Side Effects in Women
Many women report unique Lexapro side effects due to hormonal fluctuations.
Common Lexapro side effects in women include:
- Changes in menstrual cycle timing
- Increased fatigue near PMS
- Slight appetite shifts
- Headaches
- Nausea
- Sexual side effects (e.g., decreased libido)
- Increased emotional sensitivity
These same effects are sometimes searched as Lexapro side effects in females, but both refer to the same category.
Women often metabolize SSRIs differently depending on hormone levels, so tracking symptoms can be helpful during the first month.
When to Seek Medical Attention
Most first-week side effects are mild to moderate, but there are times when you should call your doctor or visit the ER.
Serious Side Effects
Contact your doctor immediately if you experience:
- Thoughts of self-harm
- Severe restlessness
- Intense anxiety or panic
- Signs of serotonin syndrome (agitation, sweating, tremors, fever)
- Rapid heart rate
- Persistent vomiting
- Severe insomnia lasting more than several days
- Unusual bleeding or bruising
If you feel unsafe or feel like harming yourself, go directly to the emergency room. Safety always comes first.
Escitalopram Interactions
Drug interactions can increase side effects. Always tell your provider about supplements and medications, including:
- Herbal supplements
- Stimulants
- Migraine medications (triptans)
- Blood thinners
- Other antidepressants
- Certain pain medications
- Alcohol
Searches for escitalopram interactions and Lexapro interactions are common because interactions can worsen fatigue, insomnia, or emotional symptoms.
Your medical provider can review your full medication list to avoid harmful combinations.
Lexapro and Constipation: Why It Happens and How to Manage It
Digestive changes are among the most frequently reported first-week side effects, and constipation, in particular, comes up often enough to warrant a closer look.
Why does Lexapro cause constipation?
Serotonin isn't just active in the brain—a large amount of the body's serotonin is actually found in the gut, where it plays a role in regulating digestion and bowel motility. When Lexapro increases serotonin availability, it can temporarily affect how the digestive system moves things along, which is why constipation, bloating, and general GI discomfort are common in the first one to two weeks.
How long does Lexapro-related constipation usually last?
For most people, digestive side effects (including constipation) are temporary and improve within the first two weeks as the body adjusts to the medication. If constipation persists well beyond that window or becomes severe, it's worth flagging to your provider.
Tips for managing constipation during the adjustment period:
- Increase water intake: Dehydration can make constipation worse, especially when paired with a new medication.
- Add fiber gradually: Fruits, vegetables, whole grains, and legumes can help, but increasing fiber too quickly can also cause bloating, so ease into it.
- Stay physically active: Even light movement like walking can help stimulate digestion.
- Consider a stool softener or gentle over-the-counter remedy if needed—but check with your pharmacist or doctor first to avoid interactions.
- Keep a consistent routine: Eating and using the bathroom at similar times each day can help regulate things.
If constipation is severe, doesn't improve after a couple of weeks, or is accompanied by significant abdominal pain, it's a good idea to check in with your provider rather than waiting it out.
Frequently Asked Questions About Lexapro Side Effects
Does Lexapro cause constipation?
Yes. Constipation is a commonly reported side effect during the first one to two weeks of starting Lexapro, related to serotonin's role in gut motility. It's usually temporary.
Can Lexapro cause constipation even at a low dose?
Yes, constipation and other GI symptoms can occur at any dose, including 5 mg, though side effects are sometimes milder at lower doses.
What does Lexapro feel like when it starts working?
Most people describe a gradual "quieting" of anxious thoughts, more emotional evenness, and more space between a stressful trigger and their reaction—rather than a sudden, dramatic change.
How long do first-week Lexapro side effects last?
Most first-week side effects, including fatigue, insomnia, and digestive changes, improve within one to two weeks as the body adjusts.
Is it normal for Lexapro to increase anxiety in the first week?
Yes, a temporary increase in anxiety during the first week is well-documented and typically improves as the body adjusts to the medication.
Summary and Final Thoughts
Starting Lexapro can feel overwhelming, especially if the first week comes with uncomfortable symptoms. However, many people find relief once their body adjusts.
Here’s what to remember:
- Lexapro side effects first week often include fatigue, insomnia, constipation, and emotional shifts.
- Most symptoms improve within 1–2 weeks.
- Escitalopram 10 mg and 20 mg are common dosages and may cause temporary side effects.
- Lexapro for anxiety can increase anxiety initially, but this is temporary.
- Women may experience unique hormonal fluctuations that affect symptoms.
- Seek medical attention for severe or worsening symptoms.
If you are navigating new medication, therapy can be an excellent support system. Working with a mental health professional—including a therapist Palm Beach Gardens or Jupiter clients trust—can help you process emotional changes, manage expectations, and build coping tools during your adjustment period.
Above all, be patient with yourself. Your first week on Lexapro is just the beginning, not the full story. With time, consistency, and support, many people experience meaningful improvements in mood, resilience, and quality of life.
