Does Strattera Cause Constipation? An In-Depth Pharmacological Review

October 8, 2025 •

3 min read

In 2023, over 3 million prescriptions for atomoxetine (Strattera) were filled in the United States [1.5.4]. For many adults starting this non-stimulant ADHD medication, a primary concern is: Does Strattera cause constipation? Yes, it is a common side effect, particularly in adults [1.2.1, 1.10.5].

Quick Summary

Strattera (atomoxetine) commonly causes constipation in adults by affecting norepinephrine levels, which can slow digestive processes [1.2.2]. This article details the mechanism, management strategies, and how it compares to stimulant medications.

Key Points

Direct Answer: Yes, Strattera is known to cause constipation, and it is listed as a common side effect in adults during clinical trials [1.2.1, 1.2.3].
Pharmacological Reason: Strattera works by increasing norepinephrine, a neurotransmitter that can slow down the digestive system's motility [1.2.2].
Adults vs. Children: Constipation from Strattera is more common in adults than in children [1.2.1, 1.5.2].
Management is Possible: The side effect can often be managed with increased fiber, water intake, and regular exercise [1.3.1, 1.3.5].
Comparison to Stimulants: Unlike Strattera, which is associated with constipation, stimulant ADHD medications are more often linked to side effects like decreased appetite and sometimes diarrhea [1.4.4].
Temporary Effect: For many individuals, side effects like constipation may diminish within a few weeks as their body adjusts to the medication [1.6.1].
Consult a Doctor: If constipation is severe or doesn't improve with lifestyle changes, it's important to speak with a healthcare provider before trying OTC remedies or stopping the medication [1.3.2, 1.3.3].

What is Strattera (Atomoxetine)?

Strattera, the brand name for the drug atomoxetine, is a non-stimulant medication approved by the FDA to treat Attention-Deficit/Hyperactivity Disorder (ADHD) in children (ages 6 and up), adolescents, and adults [1.5.5, 1.4.5]. It belongs to a class of drugs known as selective norepinephrine reuptake inhibitors (SNRIs) [1.5.5]. Unlike stimulant medications like Adderall or Ritalin, Strattera is not a controlled substance and has a low potential for abuse [1.4.4, 1.6.4]. It works by increasing the levels of norepinephrine, a natural substance in the brain that plays a role in attention, impulse control, and hyperactivity [1.5.2, 1.5.5]. The full therapeutic effects of Strattera can take several weeks to become apparent [1.4.5, 1.6.3].

The Link Explained: Does Strattera Cause Constipation?

Yes, constipation is a recognized and common side effect of Strattera, particularly for adults undergoing treatment [1.2.1, 1.10.5]. In clinical trials, constipation was one of the most frequently observed adverse reactions in adults, occurring at a rate of 5% or greater and at least twice the incidence of those taking a placebo [1.2.3]. While children can also experience this side effect, it was reported less commonly in pediatric trials [1.2.1, 1.9.5].

The Pharmacological Mechanism Behind Constipation

Strattera's primary action is to block the reuptake of norepinephrine, increasing its availability in the synaptic cleft [1.2.2, 1.4.4]. Norepinephrine is a key neurotransmitter in the sympathetic nervous system, which governs the body's "fight or flight" response. One of the functions of the sympathetic nervous system is to slow down non-essential bodily functions, including digestion. By increasing norepinephrine activity, Strattera can inadvertently slow the contractions of the muscles in the intestines (peristalsis), leading to delayed transit of stool and causing constipation [1.2.2]. Other related gastrointestinal side effects commonly reported include dry mouth and nausea [1.2.3, 1.10.1].

Comparison: Strattera vs. Stimulant ADHD Medications

When choosing an ADHD medication, understanding the different side effect profiles is crucial. While both classes of drugs can cause gastrointestinal issues, they often manifest differently.


Feature	Strattera (Atomoxetine)	Stimulants (e.g., Adderall, Vyvanse)
Drug Class	Non-Stimulant (SNRI) [1.5.5]	Stimulant [1.4.4]
Primary GI Side Effect	Constipation, dry mouth, nausea [1.2.3, 1.4.4]	Appetite suppression, stomach pain, potential for diarrhea [1.4.4, 1.4.2]
Mechanism	Increases norepinephrine levels [1.5.2]	Increases dopamine and norepinephrine levels [1.4.4, 1.4.5]
Abuse Potential	Low; not a controlled substance [1.6.4]	High; Schedule II controlled substance [1.4.4]
Onset of Action	Gradual (several weeks) [1.8.3]	Rapid (within an hour) [1.8.2]

Effective Strategies for Managing Strattera-Induced Constipation

For many, constipation caused by Strattera is manageable and may lessen over the first few weeks as the body adjusts [1.6.1, 1.6.3]. If it persists, several strategies can provide relief. Always consult your healthcare provider before starting any new supplements or over-the-counter medications.

Lifestyle and Dietary Adjustments

Increase Fiber Intake: Incorporate high-fiber foods such as fruits, vegetables, beans, and whole grains into your diet [1.3.1, 1.3.5]. Fiber supplements like psyllium (Metamucil) or methylcellulose (Citrucel) can also be effective [1.3.4, 1.3.5].
Stay Hydrated: Drinking plenty of water throughout the day is essential to help fiber work effectively and soften stool [1.3.1, 1.3.3]. Avoid dehydrating beverages like alcohol and excess caffeine [1.3.3].
Engage in Regular Exercise: Physical activity helps stimulate the natural contraction of intestinal muscles, promoting regular bowel movements [1.3.1, 1.3.5].

Over-the-Counter (OTC) Options

If lifestyle changes are not sufficient, your doctor may suggest OTC remedies [1.3.2].

Stool Softeners: Products like docusate sodium (Colace) can help by drawing water into the stool [1.3.1].
Osmotic Laxatives: Polyethylene glycol (MiraLAX) is often recommended; it works by holding more water in the stool to soften it and increase the frequency of bowel movements [1.3.1, 1.3.2].

When to Consult Your Doctor

While often mild, you should contact your doctor if constipation is severe, lasts more than a few days despite home remedies, or is accompanied by severe abdominal pain or bloating [1.3.1]. Do not stop taking Strattera abruptly without medical guidance. Your doctor might adjust your dose or, in persistent cases, explore alternative ADHD medications [1.6.3]. Other non-stimulant options include Qelbree (viloxazine), Kapvay (clonidine), and Intuniv (guanfacine) [1.8.3].

Conclusion

Constipation is a common and well-documented side effect of Strattera, stemming from its mechanism of increasing norepinephrine in the nervous system, which can slow down gut motility [1.2.2]. For most adult users, this side effect is often temporary and can be effectively managed through dietary changes, increased hydration, and regular exercise [1.3.1]. If the issue persists or becomes severe, consulting a healthcare provider is essential to discuss potential dose adjustments, OTC remedies, or alternative treatments. Open communication with your doctor ensures that your ADHD can be managed effectively while minimizing uncomfortable side effects.

For more detailed information on the drug's approved uses and side effects, you can review the official FDA drug label [1.10.1].

Frequently Asked Questions

Constipation is a common side effect for adults taking Strattera. In clinical trials, it was observed in 5% or more of adult patients, at a rate at least double that of a placebo [1.2.3].

For many people, side effects like constipation are temporary and may decrease or resolve within a few weeks as the body gets used to the medication [1.6.1, 1.6.3].

Lifestyle changes like increasing fiber and water are recommended first [1.3.1]. If those don't work, your doctor may suggest an over-the-counter stool softener like docusate or a laxative like MiraLAX. Always consult your doctor before taking new medications [1.3.2].

No, you should not stop taking Strattera without consulting your healthcare provider. They can help you manage the side effect or discuss if a dosage change or alternative medication is necessary [1.6.3].

Strattera is a selective norepinephrine reuptake inhibitor. By increasing levels of norepinephrine, it can slow down the muscle contractions in the digestive tract, leading to constipation [1.2.2, 1.5.5].

Stimulant medications for ADHD, such as Adderall or Ritalin, are not typically associated with constipation and may sometimes cause the opposite effect, like diarrhea. However, they have a different side effect profile and risk of dependency [1.4.4, 1.8.2].

Yes, staying well-hydrated by drinking plenty of water is a key recommendation for managing constipation caused by medication. Water helps soften stool, making it easier to pass, especially when you also increase your fiber intake [1.3.1, 1.3.5].