Side effects are effects that do not correspond to the intended effect and are therefore considered undesirable effects. Very often, when starting to take Ritalin, sleep disturbances and increased irritability occur. By reducing the dose or even omitting the afternoon/evening dose these symptoms can usually be reduced.
Loss of appetite is a common side effect of taking Ritalin®, but often subsides during the course of the day. Stomach pain, nausea and vomiting also occur frequently at the beginning of treatment and can be reduced if something is eaten at the same time as taking the medication, i.e. by avoiding taking it on an empty stomach. Other known side effects of taking Ritalin® are Very frequent: Frequent: Rare: In children in long-term therapy: Very rare:
- Sweating
- Lack of concentration and
- Noise sensitivity (in adults with narcolepsy)
- Change of heart rate (mostly increase)
- Palpitations
- Cardiac arrhythmias
- Changes in blood pressure (mostly increase)
- Stomach complaints
- Nausea
- Vomiting
- Dry mouth
- Hypersensitivity reactions
- Allergic skin symptoms (e.g. itching, skin rashes)
- Hair Loss
- Joint Pain
- Headaches
- Drowsiness
- Swindle
- Disturbances of the movement sequences (dyskinesias)
- Unrest
- Hyperexcitability
- Aggressiveness and
- Fever
- Reduced weight gain and growth
- Visual disorders and blurred vision
- Heart pain (angina pectoris)
- Decrease in white blood cells (leukopenia)/red blood cells (anemia)
- Decrease of blood platelets (thrombocytopenia)
- Hyperactivity
- Psychotic reactions
- Depressive moods
- Seizures
- Behavioural stereotypes
- Intensification or development of tics (muscle twitches)
- Muscle cramps
- Tourette’s syndrome
- Functional disorders of the cerebral blood vessels
- Increased dreaming
- Diarrhea
- Constipation
- Disturbed liver function
- Inflammations of the oral mucosa
- Spotty skin bleeding (thrombocytopenic purpura)
- Blistering of the skin and
- Swellings among other things with fever
Taking Ritalin® can lead to false-positive laboratory values for amphetamines, especially when an immunoassay method is used for diagnosis.
If alcohol is ingested, an unpredictable amplification of the effect can occur. During the therapy with Ritalin® alcohol should be strictly avoided. Special caution is required if the patient’s family has Gilles de la Tourette’s syndrome.
If the patient himself has not or only slightly developed the syndrome, a treatment with Ritalin® can be tested under strictest medical supervision. Even in cases of mild hypertension or motor tics (sudden, rapid muscle twitches), the use of Ritalin® is not recommended. Ritalin® can increase the readiness to cramp.
For this reason, the treatment of patients with epilepsy with Ritalin® is only recommended to a very limited extent. In individual cases, the frequency of epileptic seizures may increase. Under these circumstances, the therapy must be strictly reconsidered and Ritalin® may have to be discontinued.
If possible, Ritalin® should not be discontinued suddenly, because then the symptoms can appear as they do. If there is a congenital heart defect, children using Ritalin® are at risk of sudden death. For this reason, and due to the still unexplained mechanism, treatment with Ritalin® should not be given to children with a congenital heart defect.
The drug Ritalin® should not be used in persons with severe hypertension. Ritalin increases heart rate and systolic and diastolic blood pressure. Due to this mechanism, special caution is required in patients who may be particularly affected by hypertension or increased heart rate.
Ritalin® (methylphenidate) must not be used in patients with cardiac arrhythmia or severe angina pectoris.If there are changes in the patient’s central nervous system compared to the normal state, such as aneurysms or similar, treatment with methylphenidate (Ritalin®) is not allowed. If the patient has psychiatric disorders, treatment with Ritalin® should be avoided if possible. If psychotic symptoms such as pictorial hallucinations and hallucinations of touch occur during treatment with Ritalin, the physician should consider discontinuing the therapy.
Aggressive behavior is one of the typical symptoms of AD(H)S, but can be further aggravated or even occur in the first place with Ritalin therapy. The attending physician must carefully consider whether it would be more reasonable to stop the therapy with Ritalin® or whether a dose adjustment is sufficient. If a suicidal behavior occurs during the treatment of the patient with Ritalin®, the connection with Ritalin® must be clarified immediately by the physician and possibly a change of the kind of the treatment of the AD(H)S must be made.
The possible influence of methylphenidate (Ritalin) on the longitudinal growth of children and thus their height should be mentioned in particular. In addition, the drug Ritalin may affect weight gain in children, so regular weight and height checks are recommended for children under Ritalin treatment. Also, if patients are under long-term treatment with Ritalin, regular blood count checks, including differential blood counts, should be performed.
- Increased need for sleep
- Ravenous hunger
- Moods
- Depression
- Psychotic reactions and
- Circulatory regulation disorders
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