Introduction

When starting a new antidepressant, many people are understandably concerned about potential side effects—especially in the first week. Two of the most commonly prescribed selective serotonin reuptake inhibitors (SSRIs) are Zoloft (sertraline) and Lexapro (escitalopram). These medications are widely used to treat conditions such as depression, anxiety, panic disorder, and more. Though both are in the same class of drugs, they can affect individuals differently during the initial phase of treatment. Understanding what to expect can help users stay informed and prepared as they adjust to their new medication. In this blog, we'll compare the common first-week side effects of Lexapro vs zoloft to help you understand how they stack up.

Comparing Two ADHD Medications: Key Differences

When it comes to treating ADHD, two popular medications are Strattera vs adderall. Strattera, unlike Adderall, is a non-stimulant medication that works by affecting norepinephrine levels in the brain, offering a slower onset but with a lower risk of abuse. On the other hand, Adderall is a stimulant medication that increases the levels of both dopamine and norepinephrine, providing faster and more immediate results. Strattera vs Adderall has been a common comparison among healthcare providers, as each has its unique set of advantages depending on the individual's specific needs and health history. Both medications can be effective when managed properly.

What Are Zoloft and Lexapro?

Zoloft (generic name: sertraline) and Lexapro (generic name: escitalopram) are both SSRIs that work by increasing serotonin levels in the brain. Serotonin is a neurotransmitter involved in mood regulation, sleep, and appetite. Though they share a similar mechanism of action, they differ in their chemical structure and how they're metabolized in the body, which can lead to differences in side effects. Zoloft is often prescribed for depression, generalized anxiety disorder, PTSD, OCD, and panic disorder. Lexapro is commonly prescribed for depression and generalized anxiety disorder. Because they are both first-line treatments, many patients and healthcare providers consider the subtle differences between them when choosing which one to start.

Common First-Week Side Effects of Zoloft

During the first week on Zoloft, many people report experiencing gastrointestinal issues such as nausea, diarrhea, or upset stomach. These are among the most common early side effects and usually subside within a few days or weeks. Another frequent complaint is increased anxiety or restlessness, which might seem counterintuitive given that the drug is used to treat anxiety. This is often referred to as the “activation” effect and tends to diminish as the body adjusts. Headaches and dizziness are also not uncommon, especially when first starting or increasing the dose. Some people also report insomnia or vivid dreams in the first few nights on Zoloft. Appetite changes and slight weight loss can occur early on, though these effects vary by individual. Lastly, sexual side effects such as decreased libido or delayed orgasm can appear early but often become more pronounced with long-term use.

Common First-Week Side Effects of Lexapro

Lexapro also has its share of first-week side effects, though many users find it to be slightly more tolerable than Zoloft. The most frequently reported issues are nausea and dry mouth. Like Zoloft, Lexapro can also cause an initial increase in anxiety, nervousness, or agitation, which typically improves after the first week or two. Some people experience fatigue or drowsiness rather than insomnia, which can be problematic for those who need to be alert during the day. Lexapro is known for causing less gastrointestinal upset compared to Zoloft, but symptoms like diarrhea or constipation can still occur. Headaches and dizziness may be present but are generally mild. In terms of sexual side effects, Lexapro has a similar profile to Zoloft and may cause a decrease in libido or delayed orgasm, though individual experiences vary widely. Weight changes are less commonly reported in the first week but can occur over time.

Comparing Gastrointestinal Effects

One of the biggest complaints when starting an SSRI is gastrointestinal discomfort. Zoloft is particularly known for causing diarrhea, upset stomach, and nausea during the early days of treatment. Lexapro users tend to report fewer GI issues, though nausea is still a top complaint. For many people, taking the medication with food and staying hydrated can help ease these symptoms. The severity and duration often depend on the individual's sensitivity and whether they've taken SSRIs before. In general, Lexapro may be the better option for people who have a history of stomach sensitivity or are particularly prone to nausea.

Sleep Disturbances and Energy Levels

Zoloft and Lexapro can have different effects on sleep and energy in the first week. Zoloft may cause insomnia or restlessness, making it difficult for some people to fall asleep or stay asleep. This can be particularly frustrating for those already dealing with anxiety-related sleep problems. Lexapro, on the other hand, is more likely to cause drowsiness or fatigue in the beginning. Some patients find they feel sluggish or “foggy” during the first few days. Adjusting the time of day the medication is taken—morning for Lexapro and evening for Zoloft—can sometimes help mitigate these effects. Sleep-related side effects usually improve after the body has had time to adjust.

Mood and Anxiety Changes

Paradoxically, both Zoloft and Lexapro can initially worsen anxiety or mood symptoms before they start to improve them. This temporary spike in anxiety or irritability is a common reason why some people discontinue the medication prematurely. The mechanism behind this isn’t entirely understood, but it may be due to the sudden increase in serotonin levels affecting various parts of the brain. Zoloft users often report a more “activating” experience in the first week, while Lexapro is sometimes described as more “calming,” despite both having similar therapeutic goals. For this reason, Lexapro might be better suited for people who are highly sensitive to stimulation or those already experiencing severe anxiety.

Sexual Side Effects in the First Week

Although sexual side effects are often discussed in the context of long-term SSRI use, they can start as early as the first week. Zoloft and Lexapro both have the potential to cause decreased libido, difficulty achieving orgasm, or erectile dysfunction. These side effects don’t affect everyone and may not be noticeable right away, but some individuals are sensitive to even minor changes in sexual function. If these issues arise early and are distressing, it's worth discussing with a doctor, though they often improve over time or can be managed with dose adjustments or augmentation strategies.

Cognitive and Emotional Impact

Some users of Zoloft report feeling emotionally “blunted” or less reactive in the first week, though this is more common with continued use. Lexapro may cause a feeling of detachment or brain fog initially, especially in those starting at higher doses. While these effects can be disconcerting, they are usually short-lived. It's important to monitor how you feel mentally during the first week and keep in touch with your prescribing doctor, especially if symptoms become severe or interfere with daily functioning.

Final Thoughts

Both Zoloft and Lexapro are effective medications with proven track records in treating depression and anxiety. The first week of treatment can be challenging, but most side effects are temporary and manageable. Zoloft may be more activating and cause more gastrointestinal issues early on, while Lexapro tends to be slightly more sedating with fewer stomach-related complaints. Ultimately, the best choice depends on your personal health profile, tolerance for certain side effects, and guidance from your healthcare provider. Being informed about what to expect during the first week can help you stay the course and get the most benefit from your treatment.