Side Effects of Ritalin (methylphenidate)

Does Ritalin (methylphenidate) cause side effects?

Ritalin (methylphenidate) is a central nervous system (CNS or brain) simulant used to treat narcolepsy and children with attention-deficit hyperactivity disorder (ADHD) and to treat excessive sleepiness.

It is similar to amphetamines; however, its actions are milder than those of amphetamines. An additional difference is that Ritalin produces more noticeable effects on mental activities than on motor activities. Ritalin and amphetamines both have abuse potential. In treating children with ADHD, Ritalin produces a calming effect. This results in a reduction in hyperactivity and an improvement in attention span. 

Common side effects of Ritalin include

Serious side effects of Ritalin include

Sudden discontinuation of long-term Ritalin therapy may unmask depression. Ritalin is habit forming and should be used cautiously in individuals with a history of drug or alcohol abuse. Chronic abuse can lead to tolerance and psychological dependence leading to abnormal behavior.

Drug interactions of Ritalin include other chemicals and medications that stimulate the CNS, such as caffeine, and pseudoephedrine or phenylpropanolamine (found in many cough-and-cold preparations) because the stimulating effects of Ritalin on the CNS can be additive.

There are no adequate studies of Ritalin in pregnant women. It is unknown if Ritalin is secreted in breast milk. Consult your doctor before breastfeeding.

What are the important side effects of Ritalin (methylphenidate)?

The most common side effects with methylphenidate are:

Insomnia can be limited by taking the drug before noon. For children taking methylphenidate for ADHD, the most common side effects are

The rate and severity of these side effects are less than those seen with dextroamphetamine (Dexedrine).

Other important side effects of methylphenidate include:

There have been rare reports of Tourette's syndrome, a syndrome in which there are uncontrollable tics such as grimacing occurring with methylphenidate use. Because of the potential for side effects, methylphenidate should be used with caution by patients who have relatives with Tourette's syndrome or have the syndrome themselves or who have

Sudden discontinuation of long-term methylphenidate therapy may unmask depression. Gradual withdrawal, under supervision, is recommended.

Methylphenidate is habit forming and should be used cautiously in individuals with a history of drug or alcohol abuse. Chronic abuse can lead to tolerance and psychological dependence leading to abnormal behavior.

Priapism defined as painful and nonpainful penile erection lasting more than 4 hours, have been reported in pediatric and adult patients treated with stimulants. The erection usually resolves when the drug is stopped. Prompt medical attention is required in the event of suspected priapism.

Ritalin (methylphenidate) side effects list for healthcare professionals

The following are discussed in more detail in other sections of the labeling:

  • Abuse and Dependence
  • Known hypersensitivity to methylphenidate or other ingredients of Ritalin and Ritalin-SR
  • Hypertensive crisis with Concomitant Use of Monoamine Oxidase Inhibitors
  • Serious Cardiovascular Reactions
  • Blood Pressure and Heart Rate Increases
  • Psychiatric Adverse Reactions
  • Priapism
  • Peripheral Vasculopathy, including Raynaud's Phenomenon
  • Long-term Suppression of Growth

The following adverse reactions associated with the use of all Ritalin, Ritalin-SR, and other methylphenidate products were identified in clinical trials, spontaneous reports, and literature. Because these reactions were reported voluntarily from a population of uncertain size, it is not always possible to estimate their frequency reliably or to establish a causal relationship to drug exposure.

Adverse Reactions Reported With Ritalin And Ritalin-SR

Infections and Infestations: nasopharyngitis

Blood and the Lymphatic System Disorders: leukopenia, thrombocytopenia, anemia

Immune System Disorders: hypersensitivity reactions, including angioedema and anaphylaxis

Metabolism and Nutrition Disorders: decreased appetite, reduced weight gain, and suppression of growth during prolonged use in pediatric patients

Psychiatric Disorders: insomnia, anxiety, restlessness, agitation, psychosis (sometimes with visual and tactile hallucinations), depressed mood

Nervous System Disorders: headache, dizziness, tremor, dyskinesia including choreoatheetoid movements, drowsiness, convulsions, cerebrovascular disorders (including vasculitis, cerebral hemorrhages and cerebrovascular accidents), serotonin syndrome in combination with serotonergic drugs

Eye Disorders: blurred vision, difficulties in visual accommodation

Cardiac Disorders: tachycardia, palpitations, increased blood pressure, arrhythmias, angina pectoris

Respiratory, Thoracic and Mediastinal Disorders: cough

Gastrointestinal Disorders: dry mouth, nausea, vomiting, abdominal pain, dyspepsia

Hepatobiliary Disorders: abnormal liver function, ranging from transaminase elevation to severe hepatic injury

Skin and Subcutaneous Tissue Disorders: hyperhidrosis, pruritus, urticaria, exfoliative dermatitis, scalp hair loss, erythema multiforme rash, thrombocytopenic purpura

Musculoskeletal and Connective Tissue Disorders: arthralgia, muscle cramps, rhabdomyolysis

Investigations: weight loss (adult ADHD patients)

Additional Adverse Reactions Reported With Other Methylphenidate-Containing Products

The list below shows adverse reactions not listed for Ritalin and Ritalin-SR that have been reported with other methylphenidate-containing products.

Blood and Lymphatic Disorders: pancytopenia

Immune System Disorders: hypersensitivity reactions such as auricular swelling, bullous conditions, eruptions, exanthemas

Psychiatric Disorders: affect lability, mania, disorientation and libido

Nervous System Disorders: migraine

Eye Disorders: diplopia, mydriasis

Cardiac Disorders: sudden cardiac death, myocardial infarction, bradycardia, extrasystole

Vascular Disorders: peripheral coldness, Raynaud's phenomenon

Respiratory, Thoracic and Mediastinal Disorders: pharyngolaryngeal pain, dyspnea

Gastrointestinal Disorders: diarrhea, constipation

Skin and Subcutaneous Tissue Disorders: angioneurotic edema, erythema, fixed drug eruption

Musculoskeletal, Connective Tissue and bone Disorders: myalgia, muscle twitching

Renal and Urinary Disorders: hematuria

Reproductive System and Breast Disorders: gynecomastia

General Disorders: fatigue, hyperpyrexia

Urogenital Disorders: priapism

What drugs interact with Ritalin (methylphenidate)?

Clinically Important Interactions With Ritalin And Ritalin-SR

Table 1 presents clinically important drug interactions with Ritalin and Ritalin-SR

Table 1: Clinically Important Drug Interactions with Ritalin and Ritalin-SR

Monoamine Oxidase Inhibitors (MAOI)
Clinical Impact Concomitant use of MAOIs and CNS stimulants, including Ritalin and Ritalin-SR can cause hypertensive crisis. Potential outcomes include death, stroke, myocardial infarction, aortic dissection, ophthalmological complications, eclampsia, pulmonary edema, and renal failure.
Intervention Concomitant use of Ritalin or Ritalin-SR with monoamine oxidase inhibitors (MAOIs) or within 14 days after discontinuing MAOI treatment is contraindicated.
Examples selegiline, tranylcypromine, isocarboxazid, phenelzine, linezolid, methylene blue
Antihypertensive Drugs
Clinical Impact Ritalin and Ritalin-SR may decrease the effectiveness of drugs used to treat hypertension.
Intervention Monitor blood pressure and adjust the dosage of the antihypertensive drug as needed.
Examples Potassium-sparing and thiazide diuretics, calcium channel blockers, angiotensin-converting-enzyme (ACE) inhibitors, angiotensin II receptor blockers (ARBs), beta blockers, centrally acting alpha-2 receptor agonists
Halogenated Anesthetics
Clinical Impact Concomitant use of halogenated anesthestics and Ritalin or Ritalin-SR may increase the risk of sudden blood pressure and heart rate increase during surgery.
Intervention Avoid use of Ritalin or Ritalin-SR in patients being treated with anesthetics on the day of surgery.
Examples halothane, isoflurane, enflurane, desflurane, sevoflurane

Does Ritalin (methylphenidate) cause addiction or withdrawal symptoms?

Drug Abuse And Dependence

Controlled Substance

Ritalin and Ritalin-SR contain methylphenidate hydrochloride, a Schedule II controlled substance.


CNS stimulants, including Ritalin and Ritalin-SR, have a high potential for abuse. Abuse is characterized by impaired control over drug use despite harm, and craving.

Signs and symptoms of CNS stimulant abuse include

  • increased heart rate,
  • respiratory rate,
  • blood pressure, and/or sweating,
  • dilated pupils,
  • hyperactivity,
  • restlessness,
  • insomnia,
  • decreased appetite,
  • loss of coordination,
  • tremors,
  • flushed skin,
  • vomiting, and/or
  • abdominal pain.

Anxiety, psychosis, hostility, aggression, and suicidal or homicidal ideation have also been observed. Abusers of CNS stimulants may chew, snort, inject, or use other unapproved routes of administration which may result in overdose and death.

To reduce the abuse of CNS stimulants including Ritalin and Ritalin-SR, assess the risk of abuse prior to prescribing. After prescribing, keep careful prescription records, educate patients and their families about abuse and on proper storage and disposal of CNS stimulants, monitor for signs of abuse while on therapy, and reevaluate the need for Ritalin and Ritalin-SR use.



Tolerance (a state of adaptation in which exposure to a drug results in a reduction of the drug’s desired and/or undesired effects over time) can occur during chronic therapy with CNS stimulants, including Ritalin and Ritalin-SR.


Physical dependence (which is manifested by a withdrawal syndrome produced by abrupt cessation, rapid dose reduction, or administration of an antagonist) may occur in patients treated with CNS stimulants including Ritalin and Ritalin-SR. Withdrawal symptoms after abrupt cessation following prolonged high-dosage administration of CNS stimulants include


Ritalin (methylphenidate) is a central nervous system (CNS or brain) simulant used to treat narcolepsy and children with attention-deficit hyperactivity disorder (ADHD) and to treat excessive sleepiness. Common side effects of Ritalin include nervousness, agitation, anxiety, insomnia, loss of appetite, abdominal pain, and weight loss, nausea, vomiting, dizziness, palpitations, and headache. There are no adequate studies of Ritalin in pregnant women. It is unknown if Ritalin is secreted in breast milk.

Treatment & Diagnosis

Medications & Supplements

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Professional side effects, drug interactions, and addiction sections courtesy of the U.S. Food and Drug Administration.