Qelbree Side Effects: What to Expect and How to Manage Them
Author:
Blossom Editorial
Qelbree (viloxazine) is a once-daily, non-stimulant medication used to treat attention-deficit/hyperactivity disorder (ADHD) in adults and children ages 6 and older. Like all medications, it can cause side effects, and knowing what to expect can help you start treatment with confidence. Most effects are mild and tend to ease over time, but a few are important to watch for.
Key Takeaways
Most side effects are mild: The most common effects of Qelbree include drowsiness, insomnia, headache, tiredness, nausea, and a lower appetite. While adults may experience insomnia, headaches, dry mouth, and nausea, children may feel drowsy or irritable, have a low appetite, or have headaches or fatigue. Most side effects get better in a few weeks.
There is a boxed warning: Like other mental health medications, Qelbree carries an FDA boxed warning about a possible increase in suicidal thoughts, especially early in treatment.
It is a non-stimulant: Qelbree is not a controlled substance, so it does not carry the same risk of misuse as stimulant ADHD medications.
What is Qelbree?
Qelbree is the brand name for viloxazine, a non-stimulant ADHD medication. The U.S. Food and Drug Administration (FDA) first approved it in 2021 for children, then expanded its approval to adults. Unlike stimulant medications, it is taken once a day as an extended-release capsule.
Although the exact mechanism is not fully understood, researchers believe Qelbree (viloxazine) works mainly by increasing the levels of norepinephrine by inhibiting its reuptake (reabsorption). Norepinephrine is a neurotransmitter that supports attention and focus. Increasing norepinephrine activity is believed to improve ADHD symptoms.
However, newer studies indicate that Qelbree may affect serotonin signalling, which leads to an increase in serotonin in several areas of the brain, including the prefrontal cortex. The prefrontal cortex is a region of the brain that is responsible for executive functions that help you plan, focus, make decisions, and control impulses. Scientists believe these effects may contribute to the medication's benefits, but more research is needed to fully understand their role in treating ADHD.
Because Qelbree is not a stimulant, it is not a controlled substance, which some people and families may prefer. Another non-stimulant option in the same general category is atomoxetine (Strattera).
How Qelbree is Taken
Qelbree comes as an extended-release capsule in 100 mg, 150 mg, and 200 mg variants taken once a day, with or without food. Providers usually start with a low dose and may increase it gradually based on symptom response and side effects.
According to the FDA, for children between 6 and 11 years, the starting dose is 100 mg daily, which can be increased by 100 mg per week. For adolescents between 12 and 17 years and adults, the recommended starting dose is 200 mg daily, which may be increased by 200 mg per week, if needed. The maximum recommended dosage for children and adolescents is 400 mg/day, and for adults, 600 mg/day.
The capsule can be swallowed whole or opened and sprinkled over a spoonful of applesauce or pudding for people who have trouble swallowing pills. The FDA recommends consuming the entire food mixture without chewing within 2 hours for applesauce and 15 minutes for pudding. The capsule should not be chewed or crushed, since that can change how the medicine is released.
Sticking to the same time each day helps keep steady levels in your body and can make side effects easier to predict.
Note: Any dosing information provided is for general educational purposes only and is not a substitute for medical advice. The right dose varies based on factors such as age, symptoms, medical history, other medications, and individual response to treatment. Always follow your healthcare provider's instructions and consult them before making any changes to your medication.
Common Side Effects of Qelbree
Most people who take Qelbree have only mild side effects, and many fade within the first few weeks as the body adjusts. The exact effects can differ a little between adults and children and from person to person.
According to the FDA prescribing information, the most common side effects in adults include:
Trouble sleeping (insomnia)
Headache
Sleepiness or drowsiness
Tiredness (fatigue)
Nausea
Decreased appetite
Dry mouth
Constipation
In children and teens, the most common side effects are:
Lower appetite
Sleepiness
Trouble sleeping
Tiredness
Nausea
Vomiting
Irritability
Headache
These lists reflect the side effects that showed up most often in clinical studies by age, but that does not mean you will have any of them. Many people take Qelbree with few or no side effects at all, and those who do notice some may often find it mild. If a side effect is severe or does not settle down after the first few weeks, is is worth having a conversation with your provider rather than waiting it out on your own.
Sleep Changes and Drowsiness
Sleep-related effects are among the most common. Adults are more likely to report trouble sleeping, while children more often feel sleepy or drowsy during the day. Because of this, your provider may suggest taking Qelbree at a certain time of day. Until you know how it affects you, avoid driving or other activities that need full alertness.
Appetite and Stomach Effects
Some people notice a smaller appetite, nausea, constipation, or an upset stomach, especially when first starting. Taking the capsule with food and staying hydrated can help. In children and adolescents, providers may monitor weight and growth because decreased appetite and weight loss can occur during treatment. These effects often improve after the first few weeks.
Serious Side Effects and Warnings
Most side effects are minor, but a few need quick attention. It helps to know the warning signs before you start treatment.
Suicidal Thoughts and Mood Changes
Qelbree has a boxed warning, the FDA's strongest warning, about an increased risk of suicidal thoughts and behaviors in some pediatric and adult patients, mainly during the first few months of treatment or after a dose change. Similar boxed warnings appear on several medications that affect brain neurotransmitters, including many antidepressants. Families and caregivers should watch closely for new or worsening mood, anxiety, agitation, or talk of self-harm, and contact a provider right away if these appear.
Manic Symptoms and Other Effects
In people with a history of bipolar disorder, Qelbree may bring on manic or hypomanic symptoms, such as a racing mind, much higher energy, or unusually risky behavior. Providers usually assess patients for bipolar disorder before prescribing Qelbree.
The medication can increase heart rate and blood pressure, so your provider may check these at your visits. Rarely, it can cause an allergic reaction; seek emergency care for hives, swelling of the face or throat, or trouble breathing.
Drug Interactions to Know About
Qelbree can interact with other medications, so share a full list of what you take with your provider. It should not be used within 14 days of a type of antidepressant called a monoamine oxidase inhibitor (MAOI). Qelbree should also not be taken with medications such as linezolid (antibiotic and weak MAOI) and duloxetine (SNRI antidepressant).
Qelbree can raise the levels of certain other drugs in the body, such as the anticonvulsant phenytoin and certain treatments for asthma and heart conditions, so your provider may adjust those doses as needed. The list of possible drug interactions may also include over-the-counter products and supplements, so make sure to bring a complete list to your visit.
Who Might Consider Qelbree?
Because Qelbree is a non-stimulant, it is often considered for people with ADHD who:
Have heart problems or severe anxiety and cannot take stimulants
prefer not to take a controlled medication
have had trouble with the side effects of stimulants
have a history of substance misuse that makes stimulants less appealing
haven’t noticed improvement on stimulants
are looking for a once-daily option that lasts throughout the day
That said, non-stimulants may not be the right choice for everyone. Stimulants often begin working more quickly and, on average, may provide greater symptom improvement than non-stimulant medications for people with ADHD.
Ultimately, the most effective ADHD medication for you depends on your symptoms, health history, and preferences. A psychiatric provider can walk you through the trade-offs and help you decide. If you are not sure where to begin, our guide on how to find an ADHD psychiatrist can help.
Managing Side Effects
Many side effects can be managed with small changes and a little time. Taking your dose at a consistent time, eating regular meals, staying hydrated, and giving your body a few weeks to adjust often helps.
Your provider may also recommend ways to manage side effects. For instance, if Qelbree is causing drowsiness, you may be advised to take it at night. For insomnia, you could be asked to take the medication in the morning. Nausea may be managed by taking small, frequent meals, and constipation by taking plenty of fluids.
In any case, you should never stop Qelbree suddenly without talking to your provider, since stopping on your own can bring symptoms back. If a side effect is bothersome or does not go away, your provider may change the dose or help you explore other ADHD treatment options.
How Blossom Can Help
If you're considering switching from a stimulant medication to a non-stimulant option like Qelbree, Blossom Health can connect you with a licensed psychiatric provider who can review your symptoms, treatment history, side effects, and goals. Together, you can discuss the potential benefits and trade-offs of different ADHD medications and develop a treatment plan that fits your needs.
Medical Disclaimer
This article is for informational purposes only and is not a substitute for professional medical advice. Always seek the advice of your physician or other qualified healthcare provider with any questions you may have regarding a medical condition or medication. If you are experiencing a mental health crisis, contact the 988 Suicide and Crisis Lifeline by calling or texting 988.
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