Atomoxetine: Uses, Dosage, Recommendations, Side Effects and Interactions


It is significantly more effective than placebo and standard current therapy and does not differ significantly from or is not inferior to immediate-release methylphenidate.


Atomoxetine (Strattera) is a selective norepinephrine ( norepinephrine ) reuptake inhibitor that is not classified as a stimulant and is indicated for use in patients with attention deficit hyperactivity disorder ( ADHD ).

Atomoxetine is effective and generally well tolerated.

However, it is significantly less effective than the OROS methylphenidate extended release formulation of methylphenidate (hereinafter referred to as osmotically released methylphenidate) and the mixed extended release amphetamine salts.

Atomoxetine can be given as a single daily dose or divided into two evenly divided doses, has a negligible risk of abuse or misuse, and is not a controlled substance in the US.

Atomoxetine is particularly useful for patients at risk for substance abuse, as well as for those who have comorbid anxiety or tics, or who do not wish to take a controlled substance.

How does it work and what effects does it have on the body?

Atomoxetine can help adjust the chemicals your brain needs and focus your energy.

  • This medication is not a stimulant, which makes it different from the other medications used to treat ADHD. We are still not sure how atomoxetine works, but this is what we know so far.
  • One of the chemicals in the brain is called norepinephrine. This transmitter is released to carry messages from one cell to another in the brain.
  • After sending the message, other cells pick up the norepinephrine to stop it from working. Atomoxetine is a molecule that stops these cells from doing this. This means that the levels of norepinephrine in the brain increase.
  • Higher levels of norepinephrine in the brain help keep people alert and ready for action. They feel that they have more energy and well-being.
  • It should help increase your attention span and concentration, and prevent you from acting impulsively without thinking.
  • When the brain registers higher levels of norepinephrine, many effects occur in different parts of the body, including the heart, intestine, and lungs.

This leads to the good effects of the medicine, but it can also lead to unwanted effects (side effects). It is difficult to control how much effect occurs where. Each person is different.


You may need to take atomoxetine once or twice a day.

  • Make sure you know your dose (how many capsules to take and how many times a day to take it). This information should be written on the label of your medicine cabinet. If not, check with your pharmacist or doctor.
  • You may be taking the capsules once or twice a day.
  • Take one dose in the morning, at breakfast time.
  • Swallow the capsule with a little water, without chewing it.
  • It doesn’t matter if you take it before or after your meal.
  • If you need to take this medicine twice a day, you can take another dose in the late afternoon or evening. If you take it later in the evening, it may be difficult to fall asleep.
  • Do not open the capsule to take out the powder; dust can irritate eyes.
  • If you open a capsule, wash your hands and do not rub your eyes.
  • If you forget to take a dose, take it as soon as possible, unless you are nearing your next dose.

What to do if you miss a dose

  • If you remember later in the morning, take it as soon as possible.
  • If you forget to take it in the evening, just start again the next day.
  • If you generally take a dose in the afternoon or evening, just take the next dose when it is due.
  • Do not take a double dose to make up for doses you may have missed.

What could happen if I miss several doses?

If you forget to take it for a few days, your symptoms may return.


If you have taken more atomoxetine than it says on the label, you should get help quickly, even if you don’t feel different. Take your medicine with you, to show it to the doctors. Tell them how much you have taken. Have a friend or family member join you, if you can, in case you feel bad on the road.

You may get any of the following symptoms:

  • Upset stomach and intestines.
  • Drowsiness.
  • Dizziness.
  • Shaking
  • Unusual behavior

Atomoxetine may take 4 to 6 weeks to show its effects.

  • If you were already taking a CNS stimulant such as methylphenidate, your doctor will generally advise you to continue taking both for 4 weeks.
  • This would allow the atomoxetine to build up in your system and have a chance to start working before stopping the stimulant.
  • If you do not know – or cannot remember – how to take your medicine, or how long to continue the stimulant after starting atomoxetine, always consult your doctor.

How long should atomoxetine be taken?

Many people take atomoxetine for a few months or even years. You and your doctor should discuss how long to take atomoxetine.

  • You will not get the full effect for 4-6 weeks.
  • If you take atomoxetine for ADHD and find it helpful, your doctor will likely recommend that you take it for at least 6 months to 1 year.
  • Atomoxetine does not cure ADHD, but it does help treat symptoms. If you stop taking this medicine, your old symptoms may come back.
  • Atomoxetine does not need to be taken forever. It is important that your doctor review your treatment with you at least once a year to see if you still need it.
  • They can give you a break from the medicine; this is probably during a vacation (if you are in school or college).


You should speak to your doctor or pharmacist if any of the following apply to you. If you know you are, or think you might be, allergic to any of the ingredients (a list of ingredients can be found in the Patient Information Leaflet that comes with your medicine).

  • You have ever had heart problems (including heart defects) or a fast heartbeat.
  • You have high or low blood pressure .
  • You have a family history of heart disease or stroke.
  • You have ever had liver problems.
  • You have ever had psychotic symptoms, including hallucinations (hearing voices or seeing things that are not there), believing things that are not true, or being suspicious.
  • You have ever had mania (feeling euphoric or over-excited, causing unusual behavior) and agitation.
  • You have ever had aggressive, unpleasant, or unusual feelings of anger.
  • You have a history of epilepsy or have had fits (seizures) for any other reason.
  • Have you ever had extreme mood swings or feel very unhappy.
  • Have you ever had repetitive tremors that are difficult to control in any part of your body or repeat sounds and words.
  • You have an eye disease called narrow-angle glaucoma (increased pressure in the eye).
  • You have a tumor of your adrenal gland (pheochromocytoma).

If you have thoughts of suicide or other ways of hurting yourself, go straight to a hospital with your tablets

This can be a side effect and you need urgent help. Atomoxetine can make some people think about hurting themselves or killing themselves. This can happen to anyone, including people under the age of 18.

You should go straight to the hospital with your tablets if you have any of these thoughts. You should tell the doctor that you are taking atomoxetine. There are other things you can take instead.

Side effects

Do not stop taking atomoxetine until you talk to your doctor or you may also have withdrawal symptoms. Some side effects that appear should improve after a few days. If they don’t, you should go back to your doctor.

Very common: may affect more than 1 in 10 people.

  • Headache.
  • Drowsiness.
  • Stomach or intestinal pain, feeling or being sick.
  • Don’t feel hungry.
  • Pulse faster.
  • Dry mouth.

Common: may affect up to 1 in 10 people.

  • Feeling irritable, agitated, restless, anxious, sad, or desperate.
  • Having a low mood ( depression ).
  • Trouble sleeping, falling asleep, and waking up early.
  • Contractions that you cannot control.
  • The dilation of the pupils.
  • Upset stomach, indigestion, or constipation .
  • Feel dizzy.
  • A rash or swelling, redness, and itching of the skin.
  • Feeling tired or lazy
  • Lose weight.
  • Have chest pain.

Uncommon: likely to affect 1 in 100 people.

There are other side effects you may get from taking this drug – we have only listed the most common ones here.

Look at the leaflet inside your medicine cabinet or ask a doctor or pharmacist if you want to know if you are having a side effect with your medicine. If you get a side effect, consider reporting it to the Yellow Card scheme.

Atomoxetine can have very serious side effects

See your own doctor or go to a hospital right away if you have any of the following symptoms:

  • Feeling or having a very fast heartbeat, or uneven heartbeats.
  • Feeling aggressive, unfriendly, or very angry.
  • Have mood swings or mood swings.
  • Having a severe allergic reaction with symptoms of swelling of the face and throat.
  • Difficult breathing
  • Hives (small, raised, itchy patches of skin).
  • Fits (convulsions)
  • Psychotic symptoms including hallucinations (hearing voices or seeing things that are not there) or believing things that are not true or being paranoid.
  • With respect to men, have a painful and long-lasting erection (priapism).
  • If any of the symptoms start suddenly and get sick quickly (like shortness of breath) you (or your friend) should call for an ambulance.

Atomoxetine can sometimes cause complications with your liver, check your liver health

Atomoxetine can sometimes cause problems with your liver. This side effect is rare but serious, so it is important that you know it and what to do if you think it is a problem for you.

Tell your doctor before you start taking atomoxetine if you have ever had liver problems; you may be given a lower dose. Your doctor may suggest that you have regular blood tests to check how well your liver is working.

Be on the lookout for any of these side effects that could indicate that your liver is not working as well as it could. See a doctor immediately if you get any of them:

  • Pain in the stomach or intestine that hurts if you press it on the right side just below the ribs.
  • Feeling sick for no obvious reason.
  • You usually don’t feel well – you feel tired or like you have the flu.
  • Itch.
  • Your urine is darker than normal.
  • The whites of your eyes or skin start to look a little yellow (jaundice).
  • Some side effects that appear should improve after a few days.
  • If they don’t or they get worse, you should see your doctor.
  • If you have any side effects not mentioned here, check the patient leaflet in the medicine pack.

Some atomoxetine side effects may seem, strangely, like symptoms of other mental health conditions. Some side effects here are also the opposite of each other (for example, it could cause drowsiness or trouble falling asleep).

The balance of chemicals in the brain is very fragile and difficult to control. If they don’t improve after a few days on the tablets, go back to the doctor.

Monitor your heart status regularly when taking atomoxetine.

Before starting treatment, your doctor should check your blood pressure and heart rate (pulse). They should also take note of your weight and height.

  • Your doctor should check your blood pressure and heart rate (pulse) if your dose of medicine has changed and at least every 6 months for as long as you take atomoxetine.
  • You will also check your weight and height at least every 6 months, but you can do it more often.
  • Stopping the drug causes the balance of chemicals in the brain to upset.
  • Once you start taking atomoxetine, your brain adjusts to a new level of norepinephrine.
  • If you stop taking atomoxetine all at once, the balance starts to change again.

Side effects are not reported to occur if you suddenly stop atomoxetine, but your previous symptoms may return.

If you no longer want to take this medicine, it is important to talk to your doctor about it. It is not a good idea to suddenly stop taking your medicine without consulting your doctor.

Young people are more likely than adults to have some side effects on tests

Young people and children were more likely than adults to have the following side effects:

  • Mood swings or changes in mood.
  • Self-harming or suicidal behaviors or thoughts.

Atomoxetine may cause growth retardation at the start of treatment.

Some young people have experienced delayed weight and height growth when they start taking atomoxetine. This has been linked to having a decreased appetite, a side effect of the drug. Over time, these young people have recovered and their growth returns to normal.

Make sure to check your height and weight before you start taking atomoxetine, and while taking it. Sometimes the doctor may stop the drug or change the dose for a time so that you can regain weight and height, and then start it again.

Effects on sex life

Atomoxetine can also have side effects that can affect your sex life. The good effects of atomoxetine can have a good effect on your sex life as your symptoms stabilize and you can focus on your relationships.

There are some side effects including:

  • Men may have pain in their sexual organs, or painful erections that last a long time.
  • You may feel too tired to have sex.

These effects should pass after the first couple of weeks. If they don’t, and this is a problem for you, go back to the doctor and see what else you can try. However, if you have an erection that is painful and does not go away, you should see a doctor as soon as possible for treatment.


Do not take atomoxetine if you take any of the following medications:

  • If you took a medicine known as a monoamine oxidase inhibitor (MAOI) for low mood (depression), such as phenelzine, in the last two weeks.

Other medicines may not mix well with atomoxetine. Tell your doctor or pharmacist if you are taking any of the following:

  • Medicines that increase blood pressure or are used to control blood pressure.
  • Antidepressants such as imipramine, venlafaxine, mirtazapine , fluoxetine or paroxetine.
  • Antipsychotics such as haloperidol, chlorpromazine, risperidone which can affect the heart.
  • The antimalarial medicine quinidine.
  • Terbinafine antifungal medicine (tablets or creams).
  • Salbutamol (to treat asthma) (tablets or inhalers).
  • Medicines used to control the rhythm of the heart.
  • Some antibiotics (such as erythromycin or moxifloxacin).
  • Some pain relievers (tramadol).
  • Methadone.
  • Cough and cold remedies that you can buy at a grocery store or pharmacy that contain decongestants such as pseudoephedrine or phenylephrine.

If you have any further questions, you should speak to your doctor or pharmacist. Always talk to your doctor if you are taking other medications.

If you buy medicines (including those you put on the skin) for common ailments, it’s always best to get them from a pharmacy (and not a supermarket or general store).

Always inform the pharmacist that you are taking atomoxetine so they can make sure that anything they sell you is safe to take with this medicine.

Pregnancy, fertility and breastfeeding

It is not known if atomoxetine can affect fertility.

  • No effects on fertility have been observed in animal studies.
  • There is no information on humans to know if there are effects on fertility.
  • It is not known if atomoxetine can cause side effects in developing babies or newborns, or if atomoxetine is passed to the baby in breast milk.

It is recommended not to breastfeed if you are taking atomoxetine.

It is not known if atomoxetine is passed to the baby in breast milk, and if so, we do not know if it could be harmful to the baby. If it is important for you to breastfeed, talk to your doctor or midwife as soon as possible.

Do not take atomoxetine if you are trying to get pregnant.

There is not enough information to know whether it is dangerous or not to take atomoxetine during pregnancy. Talk to your doctor if you are trying to get pregnant; This is very important because they can help you make a decision about your medicine, which is the best one for you.

If you find out that you are pregnant while taking atomoxetine, you should see your own doctor to discuss this.

Other things to keep in mind while taking atomoxetine


If you drink alcohol, you can continue to drink alcohol while taking atomoxetine, but having the two together can make you very sleepy. So for the first few days, it would be best to stop drinking alcohol until you see how the medicine affects you.

If you want to drink alcohol, remember that you can be sleepy and make sure you can get home safely.

Driving vehicles or handling dangerous instruments

Do not drive a car, ride a bicycle, or handle dangerous instruments right after you start taking atomoxetine.

Taking atomoxetine can make you feel tired or dizzy when you start taking it. This could affect you if you drive a car, ride a bike, or do anything else that requires a lot of concentration. It may be best to stop doing these things for the first few days, until you know how it affects you.

Don’t worry: most people do these things normally while taking atomoxetine.

Atomoxetine and sports

Atomoxetine is not a prohibited substance in sport. However, you may feel tired or dizzy at first, so this could cause a problem in sports where you need a lot of focus.

It may be best to stop doing these sports for a short time until you know how the medicine affects you. Don’t worry: most people do all of this normally while taking atomoxetine.


Your weight can be affected by atomoxetine. A side effect of atomoxetine can be weight loss. Talk to your doctor if you are concerned.

Sleep related problems

Atomoxetine can make you tired and sleepy. It has also made it difficult for some people to fall asleep or stay asleep. Talk to your doctor if it’s a problem for you.

Let your family and friends know that you are taking atomoxetine so they can support you and help you detect side effects.

The side effects of atomoxetine can put pressure on your friendships and relationships, especially in the first few days of taking it. You may feel angry, unpleasant, or have mood swings. These side effects should improve after a few days.

You should get the good effects of atomoxetine, and that should improve your relationships in and of itself. It may actually be a good idea to choose a good friend to tell you about your medication when you start taking it (or, better yet, take one with you to the doctor before you start taking it).

They may help you understand if the medicine changes your behavior or causes side effects (sometimes it’s hard for us to see for ourselves). Atomoxetine is not a CNS stimulant, but it does affect the balance of chemicals in the brain.