Side effects of Ritalin®

Side effects are seen as effects that do not correspond to the intended effect and are thus seen as undesirable effects.

Very often, when you start taking Ritalin, you experience difficulty sleeping and increased irritability. These symptoms can usually be reduced by reducing the dose or omitting the afternoon / evening dose.

Loss of appetite is a common side effect of taking Ritalin®, but it often subsides over the course of the day.

Stomach pain, nausea and vomiting are also common at the beginning of treatment and can be reduced if something is eaten at the same time as the medication, i.e. by avoiding ingestion on an empty stomach.

Other previously known side effects when taking Ritalin® are:

Very often:

  • sweat
  • Lack of concentration and
  • Sensitivity to noise (in adults with narcolepsy)


  • Change in heart rate (mostly increase)
  • Palpitations
  • Cardiac arrhythmias
  • Changes in blood pressure (mostly increase)
  • Stomach discomfort
  • nausea
  • Vomit
  • Dry mouth
  • Hypersensitivity reactions
  • allergic skin symptoms (e.g. itching, skin rashes)
  • Hair loss
  • Joint pain
  • a headache
  • sleepiness
  • dizziness
  • Disorders of the movement sequences (Dyskinesia)
  • Restlessness
  • Overexcitability
  • aggressiveness and
  • fever

Rare: For children in long-term therapy:

  • decreased weight gain and decreased growth
  • Visual disturbances and blurred vision
  • Heart pain (Angina pectoris)

Very rare:

  • Low number of white blood cells (leukopenia) / red blood cells (anemia)
  • Decrease in blood platelets (Thrombocytopenia)
  • Hyperactivity
  • psychotic reactions
  • depressive moods
  • Seizures
  • Behavioral stereotypes
  • Increase or development of tics (Muscle twitching)
  • Muscle spasms
  • Tourette syndrome
  • Malfunction of the cerebral blood vessels
  • increased dreaming
  • diarrhea
  • constipation
  • impaired liver function
  • Inflammation of the lining of the mouth
  • punctiform skin bleeding (thrombocytopenic purpura)
  • Blistering of the skin and
  • Swelling i.a. with fever

Special information on therapy with Ritalin®

Taking Ritalin® can cause it to false positive laboratory values for amphetamines, especially when an immunoassay method is used for diagnostics.

Becomes alcohol ingested so it can become a unpredictable amplification of effects come. During the Therapy with Ritalin® is therefore strict on alcohol to renounce.

Particular caution should be exercised if this occurs in the patient's family Gilles de la Tourette syndrome is known. If the patient has not developed the syndrome or has only slightly developed it, a treatment attempt with Ritalin® can be tested under the strictest specialist supervision.

Even with mild high blood pressure or motor tics (sudden, rapid muscle twitches) is one Use of Ritalin® not recommended. With Ritalin®, the Convulsive readiness increase. Because of this, the treatment of patients with epilepsy with Ritalin® only highly recommended. In individual cases, the epileptic seizures increase in frequency. Under these circumstances, the therapy must be carefully reconsidered and the Ritalin® may be discontinued.

It should be possible no sudden withdrawal from Ritalin®, because then the symptoms like

  • increased need for sleep
  • Cravings
  • Upset
  • depression
  • psychotic reactions and
  • Circulatory regulation disorders

may occur.

Lies a congenital heart defect there is a risk of sudden death in children using Ritalin®. For this reason and the as yet unexplained mechanism, treatment with Ritalin® should not be used in children with congenital heart defects.

The drug Ritalin® must not be used in people with severe high blood pressure. By taking Ritalin the heart rate increases and the systolic and diastolic blood pressure. Because of this mechanism, special care should be taken in patients suffering from high blood pressure or increased heart rate could be particularly affected.

At Cardiac arrhythmias and heavier Angina pectoris Ritalin® (methylphenidate) must not be used. Exist in Central nervous system of the patient's changes compared to normal, such as, for example Aneurysms or similar, must not be treated with methylphenidate (Ritalin®).

If the patient has psychiatric illnesses, treatment with Ritalin® should be avoided if possible. Occur under treatment with Ritalin psychotic symptoms like figurative Hallucinations and Hallucinations If the sense of touch occurs, the doctor should consider discontinuing the therapy.

Aggressive behavior in particular is within the scope of AD (H) S one of the typical symptoms, however, therapy with Ritalin can make it worse or even appear in the first place. The attending physician must carefully consider whether a Termination of therapy Ritalin® might be more sensible or a dose adjustment is sufficient.

Occurs while the patient is being treated with Ritalin® suicidal behavior the connection with the Ritalin® must be clarified by the doctor immediately and the type of treatment for AD (H) D may be changed.

Particularly noteworthy is the possible influence of methylphenidate (Ritalin) on this Growth in length in children and thus the body size. The drug Ritalin may also affect weight gain in children, which is why regular checks of weight and height recommended for children taking Ritalin. If patients are treated with Ritalin for a longer period of time, the Blood count, included Differential blood count, respectively.

Side effects on the heart

Everywhere in the body there are transporters that take up messenger substances again, including those in the heart. Ritalin also inhibits the transporters on the heart, depending on the dosage.
Norepinephrine in particular activates receptors on the arteries, the so-called resistance vessels, and thus causes blood pressure to rise. However, even at higher concentrations, it acts directly on the receptors of the heart, as well as on receptors on the kidneys, which among other things also play an important role in terms of blood pressure and cardiac output.
With a high dopamine concentration, dopamine also docks onto all of these receptors. This stimulates the heart. If the excitation of the heart is too pronounced, this can lead to disturbances.
A frequent side effect of Ritalin® could be palpitations, the so-called tachycardia, increased blood pressure and arrhythmias, arrhythmias. to be watched at heart. If Ritalin® is suddenly stopped, it can occasionally cause circulatory disorders. Chest pain called angina pectoris attacks has been reported less frequently.
The long-term effects of Ritalin® on the heart cannot yet be adequately assessed. A heart examination is mandatory before and during treatment with Ritalin®, as well as with every dose adjustment. Therefore, heart rate and blood pressure should be recorded at least every 6 months.

Side effects on the eyes

Ritalin® can also affect the eyes. Other side effects included visual disturbances and blurred vision. Since sympathetic receptors are also located on the eye, overstimulation of the receptors and thus impaired vision can occur in some rare cases. Furthermore, Ritalin® can trigger a dilation of the pupils, which does not necessarily have to lead to restrictions.

Side effects on the skin

Hair loss was often reported as a side effect of Ritalin®. In some cases, there were also wheals on the skin. These rashes, known as hives or urticaria, were often causing itching.

Sweating as a side effect

A very common side effect of taking Ritalin® is increased sweating. The active ingredient in Ritalin® is one of the so-called indirect sympathomimetics. This means that Ritalin stimulates sympathetic activity. In principle, the sympathetic system causes everything that is essential for escape and combat situations. This also means that the body can cool down by sweating. This is exactly what can happen by stimulating the sympathetic nervous system with drugs. This happens regardless of whether the person is currently in an escape and combat situation or not. If the sweating is very pronounced, there may be a loss of salt. Consultation with the attending physician is advisable. The dose of Ritalin® may need to be reduced.

How does Ritalin® affect learning?

According to some authors, Ritalin® should help you learn more efficiently. There is controversy as to whether this is actually the case. It is known that the active ingredient in Ritalin®, the so-called methylphenidate, affects the nerve cells in the brain. The processes at cell level could thus have an impact on learning.
It is believed that the active ingredient in Ritalin inhibits transporters in the nerve cells that take up various messenger substances back into the cell. This means that Ritalin® blocks the reuptake of messenger substances such as dopamine and norepinephrine. As a result, these messenger substances remain in the so-called synaptic gap longer and the messenger substances can act longer on the corresponding receptors. As a result, the concentrations of these messenger substances increase. In addition, one suspects an effect on the receptors on which the messenger substance serotonin acts.
To a limited extent, the increased dopamine could trigger feelings of happiness while studying. Norepinephrine increases drive, which could have a positive effect on the drive to learn. Serotonin also increases drive in higher concentrations. But if serotonin is present in larger amounts for a long time, it is assumed that it reduces its own receptors. This then ultimately has an anti-anxiety effect. The messenger substance causes the vessels to expand at other receptors. This can lead to improved blood flow. As a result, a relatively relaxed basic state and increased concentration through better blood circulation in blood vessels could be achieved during learning.
People taking Ritalin® report that they noticed how they could concentrate better. Many had less need for sleep, less hunger and thirst, and less pain.
But the increased concentration of messenger substances could, in addition to the side effects that should not be underestimated, also have negative effects on learning. Too high a noradrenaline concentration can result in tasks being solved without thinking about it in detail. In addition, an imbalance in the messenger substances could have unpredictable effects on learning. In addition, the long-term effects on nerve cells and other cells are not fully understood. Long-term reduced performance of the nerve cells and thus a decline in various thinking functions cannot be completely ruled out.

What happens in the event of an overdose?

In the case of overdoses, the side effects can be more pronounced. Overdosing by doubling the dose once may cause palpitations, dizziness, sleep disturbances, increased wakefulness or excessive sedation and drowsiness. Since the duration of the effect of Ritalin® usually only lasts a few hours, the side effects of the overdose have disappeared afterwards. If this is not the case or if there is any doubt, a doctor should be contacted.
An overdose of more than a single double dose can have serious consequences. Colloquially, it can lead to a “thunderstorm in the brain”. This can manifest itself with epileptic convulsions, impaired consciousness and even coma. In addition, there can be a "thunderstorm in the heart" with cardiac arrhythmias. In these cases, immediate medical treatment is absolutely necessary.

Interactions of Ritalin® with other drugs

Through the active ingredient Methylphenidate in Ritalin® the Effectiveness of other drugs impaired become. These include:

  • anticoagulants (Coumarins)
  • Means for treating epilepsy (including phenobarbital, phenytoin, primidone)
  • Neuroleptics (e.g. Haloperidol®)
  • Antidepressants (Imipramin®, Desipramine®)
  • Phenylbutazone
  • Carbamazepine
  • Antacids

Ritalin® during pregnancy

The drug Ritalin® is during the pregnancy not indicated and women of childbearing potential should take an safe method of contraception apply.

Ritalin® during breastfeeding

Since it has not yet been clarified to what extent methylphenidate (Ritalin®) enters the Breast milk should be discontinued before taking Ritalin® or with taking Ritalin® up to Ending the breastfeeding period to be waited for a possible avoid negative influence on the child.