How Zoloft (Sertraline) Works

Zoloft is a medication sometimes prescribed to treat depression, anxiety, and other conditions. It works by preventing the reuptake of serotonin, a neurotransmitter that affects mood. By preventing reuptake, Zoloft can increase the amount of serotonin available in the brain.

Zoloft (sertraline) is a selective serotonin reuptake inhibitor (SSRI). Although it is most commonly used to treat depression, it is also used to treat obsessive-compulsive disorder (OCD), panic disorder, and post-traumatic stress disorder (PTSD). Zoloft is sometimes prescribed for social anxiety disorder and other phobias.

This article discusses how Zoloft works and possible side effects you might experience. It also covers important precautions to be aware of before taking this medication.

How Does Zoloft Work?

SSRIs are known as second-generation antidepressants since they are newer than monoamine oxidase inhibitors (MAOIs) and tricyclic antidepressants (TCAs). 

Serotonin is a chemical neurotransmitter that transmits electrical impulses from one neuron to the next. Normally, serotonin is quickly reabsorbed, but Zoloft and other antidepressants in this class let the serotonin remain in the synaptic gap between neurons for longer.

This allows the chemical to send additional messages to the receiving neuron, which is thought to boost mood.

How Can You Tell if Zoloft Works?

After you first start taking Zoloft, you may experience some daytime sleepiness. However, some people have the opposite effect and experience increased energy and sleeping problems. 

Your doctor may recommend changing when you take your medication depending on the effect you experience. They may suggest taking it at night before bed if it makes you feel fatigued. If you feel energized, taking it in the morning is better so it is less likely to interfere with your sleep.

Zoloft takes time to work, so you may wonder how to tell if your medication is helping. After a few weeks, you may feel less depressed or anxious. You may have more energy and motivation. Sleep improvements and a better appetite are changes you may see during your first month or so of taking your medication.

It is important to remember that these changes tend to be gradual. They may happen slowly, sometimes making it more difficult to notice the improvements you are experiencing.

How Much Zoloft Do You Need to Take?

Zoloft is available in a variety of strengths and is only sold by prescription. Both liquid and tablet forms of the medication are available.

Your dosage will depend on what you are being treated for. Standard dosages for different mood disorders are:

• Major depressive disorder: 50 to 200 mg daily
• Obsessive-compulsive disorder: 50 to 200 mg daily
• Post-traumatic stress disorder: 50 to 200 mg daily
• Pre-menstrual dysphoric disorder: 50 to 100 mg daily during the luteal phase
• Social anxiety disorder: 50 to 200 mg daily

Zoloft tablets are available in 25 mg, 50 mg, and 100 mg doses. Your doctor may start you at a lower dose and gradually increase the amount you take to achieve the desired effects.

You may or may not quickly begin to feel the effects. Talk to your doctor if you have any concerns.

How Long Does it Take for Zoloft to Work?

Zoloft does not begin working immediately. It takes time for the medication to reach a steady state in your body and gradually increase the serotonin in your brain. Like all medications in its class, Zoloft does not perform optimally until you have taken it consistently for several weeks.

The first changes you might notice include improvements in appetite, sleep, and energy levels. However, if you do not see any noticeable improvement after several weeks, talk to your doctor.

Zoloft Drug Interactions

Avoid the liquid formulation of Zoloft if you are on Antabuse (disulfiram) because it contains alcohol. Wait at least 14 days after your last dose of any MAOI before beginning sertraline treatment.

Zoloft interacts with a wide range of natural remedies. Ask your doctor before taking tryptophan, St. John's wort, or any other herbal or natural formulation.

In addition, Zoloft interacts with numerous prescription and over-the-counter medications, including NSAID pain relievers, diuretics, stomach medicines, blood thinners, and treatments for certain mental illnesses.

Zoloft can also interact with other medications and substances that increase serotonin levels, including other antidepressants. If serotonin levels become too high, you may experience serotonin syndrome. Serotonin syndrome can be life-threatening and lead to symptoms such as anxiety, confusion, fever, high blood pressure, irregular heartbeat, and seizures.

Precautions Before You Take Zoloft

Since 2005, all SSRIs have carried "black box" warnings from the FDA regarding a higher risk for suicidal ideation and behavior in children. The FDA expanded its warning in 2007 to include young adults under the age of 25.

Although many young people successfully take these common medications, informed consent is important. Discuss the benefits and risks with your child's doctor before making a decision.

Your risks from Zoloft may be higher if you have certain medical conditions, including diabetes, low blood sodium levels, seizures, and liver disease. Give your doctor a full medical history of all current and previous illnesses.

Also, let your doctor know if you have a history of drug abuse. If you are currently breastfeeding or pregnant, or if you plan to become pregnant, discuss the risks and benefits of treatment with your physician.

Side Effects When Taking Zoloft

Like all medicines, Zoloft carries a risk for side effects. Common side effects such as headache, sleep difficulties, dry mouth, sweating, and loss of appetite are typically mild and may subside in a few days or weeks.

What Happens if You Stop Taking Zoloft?

All SSRIs, including Zoloft, carry a risk for a collection of withdrawal symptoms known as SSRI discontinuation syndrome. Common sertraline withdrawal symptoms include odd electrical sensations known as "brain jolts" or "brain zaps," dizziness, and headaches.

Although the syndrome is not generally considered dangerous, the symptoms can be distressing. Don't lower your dose or suddenly stop taking Zoloft without your doctor's approval.

If you stop taking Zoloft, it is also possible that you may experience a return of symptoms. If you begin experiencing depression, anxiety, or other mental health concerns. They may recommend resuming your medication, switching to a different type of antidepressant, or treating your condition with psychotherapy.