Ritalin (methylphenidate) is a prescription drug that’s used to treat narcolepsy and ADHD. Ritalin can cause side effects that range from mild to serious. Examples include headache and the risk of misuse and addiction.

Ritalin is used in adults and certain children to treat:

The active ingredient in Ritalin is methylphenidate. (An active ingredient is what makes a drug work.) The drug comes in two forms:

  • Ritalin oral tablet
  • Ritalin LA extended-release* oral capsule

Unless stated otherwise in this article, the term “Ritalin” is used for both forms of the drug.

Keep reading to learn about the common, mild, and serious side effects that Ritalin can cause. For a general overview of the drug, including details about its uses, see this article.

* “Extended release” means the drug is slowly released into your body over a period of time.

Below are just a few of the more common side effects reported by people who took Ritalin or Ritalin LA in studies.

  • heart problems, such as:
    • increased heart rate
    • palpitations (a feeling of skipped or extra heartbeats)
  • headache*
  • insomnia (trouble sleeping)*
  • upper abdominal pain
  • reduced appetite

* To learn more about this side effect, see the “Side effects explained” section below.

Mild side effects have been reported with Ritalin and Ritalin LA. These include:

In most cases, these side effects should be temporary. And some may be easily managed. But if you have symptoms that are ongoing or bothersome, talk with your doctor or pharmacist. And do not stop taking Ritalin unless your doctor recommends it.

Ritalin may cause mild side effects other than those listed above. For details, see the prescribing information for Ritalin and Ritalin LA.

* To learn more about this side effect, see the “Side effects explained” section below.
† An allergic reaction is possible after taking Ritalin. This side effect wasn’t reported in studies of Ritalin or Ritalin LA but has been reported since the drugs were approved.

Serious side effects have been reported with Ritalin and Ritalin LA. These include:

If you develop serious side effects while taking Ritalin, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

* To learn more about this side effect, see the “Ritalin and misuse” section below.
† To learn more about this side effect, see the “Side effects explained” section below.
‡ An allergic reaction is possible after taking Ritalin. This side effect wasn’t reported in studies of Ritalin or Ritalin LA but has been reported since the drugs were approved.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. If you’d like to notify the FDA about a side effect you’ve had with Ritalin, visit MedWatch.

Ritalin is used to treat narcolepsy and attention deficit hyperactivity disorder (ADHD) in children ages 6 years and older. Ritalin LA is used to treat ADHD in children ages 6–12 years.

Many side effects of Ritalin and Ritalin LA are similar in children and adults. Examples are listed in the “What are the mild side effects of Ritalin?” and “What are the serious side effects of Ritalin?” sections above.

Rarely, slowed growth has been reported in children taking stimulant drugs. (Ritalin and Ritalin LA are stimulants.) Due to this risk, your child’s doctor will check their weight and height during Ritalin treatment. If your child shows signs of slowed growth, your child’s doctor may have them stop taking the drug.

For more information about potential side effects of Ritalin in children, talk with your child’s doctor or a pharmacist.

Get answers to some frequently asked questions about Ritalin’s side effects.

How do side effects of Ritalin seen in females compare with those seen in males?

Most of Ritalin’s side effects in females* are expected to be the same as the side effects seen in males.* But in rare cases, Ritalin may cause priapism in males.

Priapism is a painful erection that lasts for more than 4 hours. Certain factors can increase the risk of priapism when taking this drug. These include taking Ritalin long term, having your dosage increased, or suddenly stopping treatment.

In extreme cases or if left untreated, priapism may cause permanent tissue damage. If you have priapism during Ritalin treatment, seek emergency medical care right away. Your doctor will likely advise you to stop Ritalin treatment and recommend alternative options.

If you have other questions about the side effects of Ritalin in females and males, talk with your doctor or pharmacist.

* In this article, we use the terms “female” and “male” to refer to someone’s sex assigned at birth. For information about the difference between sex and gender, see this article.

Does Ritalin cause long-term side effects?

Yes, it’s possible. Long-term side effects include those that may start at any time you’re taking a drug, even if you’ve taken it for a long time. It also includes side effects that may not go away, even after you stop taking the drug.

Examples of long-term side effects reported in studies of Ritalin and Ritalin LA include:

  • priapism (painful and long lasting erection)
  • slowed growth in children*

Talk with your doctor to learn more about possible side effects of Ritalin and how long they may last.

* To learn more, see the “Side effects in children” section above.

Learn more about some of the side effects Ritalin may cause.

Headache

Headache was a common side effect reported in studies of Ritalin and Ritalin LA. With headache, you may have a dull, throbbing, or sharp pain or pressure in your head.

What might help

If you have a bothersome or long lasting headache during Ritalin treatment, talk with your doctor. They can recommend over-the-counter options to help relieve your symptoms. Examples include Tylenol (acetaminophen) and Advil (ibuprofen). They may also suggest home remedies to ease your symptoms.

Insomnia

Insomnia was a common side effect reported in studies of Ritalin and Ritalin LA. With insomnia, you may have trouble falling asleep or staying asleep. This may lead to other symptoms, such as irritability and fatigue (low energy).

What might help

If you have insomnia during Ritalin treatment, talk with your doctor. They can suggest ways to help manage this side effect. For example, they’ll likely suggest taking your Ritalin dosage early in the day to lower the drug’s effect on your sleep.

Your doctor can tell you about other possible remedies for insomnia.

Allergic reaction

Like most drugs, Ritalin can cause an allergic reaction in some people. This side effect wasn’t reported in studies of Ritalin or Ritalin LA but has been reported since the drugs were approved. Symptoms can be mild to serious and can include:

  • skin rash
  • itchiness
  • flushing (temporary warmth, redness, or deepening of skin color)
  • swelling under your skin (usually in your eyelids, lips, hands, or feet)
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms. Examples include:

  • an oral antihistamine, such as Benadryl (diphenhydramine)
  • a product you apply to your skin, such as hydrocortisone cream

If your doctor confirms you’ve had a mild allergic reaction to Ritalin, they’ll decide if you should continue taking it.

If you have symptoms of a severe allergic reaction, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to Ritalin, they may have you switch to a different treatment.

Keeping track of side effects

During your Ritalin treatment, consider taking notes on any side effects you’re having. You can then share this information with your doctor. This is especially helpful when you first start taking a new drug or using a combination of treatments.

Your side effect notes can include things such as:

  • what dose of the drug you were taking when you had the side effect
  • how soon you had the side effect after starting that dose
  • what your symptoms were
  • how your symptoms affected your daily activities
  • what other medications you were taking
  • any other information you feel is important

Keeping notes and sharing them with your doctor will help them learn more about how Ritalin affects you. They can then use this information to adjust your treatment plan if needed.

Below is important information you should consider before starting Ritalin.

Boxed warning: Risk of misuse and addiction

Ritalin has a boxed warning about the risk of misuse and addiction. A boxed warning is the most serious warning from the Food and Drug Administration (FDA).

Misuse refers to taking a drug in a way other than how a doctor prescribes it. With addiction, a drug is used even if it’s causing harmful outcomes.

To learn more, see the “Ritalin and misuse” section below.

Other warnings

Ritalin can sometimes cause harmful effects in people with certain conditions. This is known as a drug-condition interaction. Other factors may also affect whether Ritalin is a good treatment option for you.

Talk with your doctor about your health history before starting this medication. Be sure to tell them if any of the following factors apply to you:

Alcohol and Ritalin

Talk with your doctor before consuming alcohol during Ritalin treatment. Ritalin and alcohol work in opposite ways, so each may mask the other’s effects. As a result, drinking alcohol while taking Ritalin could make it hard to tell whether Ritalin is working for your condition. Likewise, taking Ritalin could make it hard to know the amount of alcohol you’ve consumed.

You should avoid consuming alcohol if you’re taking Ritalin LA. Alcohol may cause most of Ritalin LA to be released into your body right after you take it. This effect could increase your risk of side effects from the drug. Examples include dry mouth, headache, and excessive sweating.

If you have questions about consuming alcohol during Ritalin treatment, talk with your doctor or pharmacist.

Pregnancy and breastfeeding with Ritalin

There is limited information about the safety of Ritalin use during pregnancy or while breastfeeding.

Pregnancy

It’s not known whether it’s safe to take Ritalin during pregnancy. If you’re pregnant or planning to become pregnant, talk with your doctor before starting treatment with Ritalin.

If you take this drug while pregnant, consider signing up for The National Pregnancy Registry for ADHD Medications. You can do so by visiting the website or calling 866-961-2388. A pregnancy registry collects information about the safety of certain drugs when used during pregnancy.

Breastfeeding

It isn’t known whether Ritalin is safe to take while breastfeeding. If you’re breastfeeding or planning to do so, talk with your doctor before starting this medication.

Ritalin has a boxed warning for the risk of misuse* and addiction.* A boxed warning is the most serious warning from the Food and Drug Administration (FDA). Ritalin is a Schedule II controlled substance and has a high risk of misuse during treatment. Examples of misuse include using the drug more often or at higher doses than recommended by your doctor.

Symptoms of misuse and addiction may include:

You should take Ritalin only as your doctor has prescribed. Misuse raises the risk of overdose, which can lead to trouble breathing, coma, and even death. To learn more about this risk, talk with your doctor or pharmacist.

* Misuse refers to taking a drug in a way other than how a doctor prescribes it. With addiction, a drug is used even if it’s causing harmful outcomes.

Help is out there

If you or someone you know is in crisis and considering suicide or self-harm, please seek support:

If you’re calling on behalf of someone else, stay with them until help arrives. You may remove weapons or substances that can cause harm if you can do so safely.

If you are not in the same household, stay on the phone with them until help arrives.

Like most drugs, Ritalin can cause a number of side effects that range from mild to serious. But most are temporary and go away after a few days to weeks. If you have questions about side effects that Ritalin can cause, talk with your doctor. Examples of questions to help get you started include:

  • Do any other medications I take increase my risk of side effects from Ritalin?
  • Do any health conditions I have raise my risk of side effects from Ritalin?
  • Do I have any factors that increase my risk of misuse or addiction with Ritalin?

To get information on different conditions and tips for improving your health, subscribe to any of Healthline’s newsletters. You may also want to check out the online communities at Bezzy. It’s a place where people with certain conditions can find support and connect with others.

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.