http://www.adhd-report.com/adhd/ritalin/29_ritalin_side_effects.html

Cardiovascular Side Effects of Ritalin

1.Rapid heart beat (palpitations, tachycardia)
2.High blood pressure (hypertension)
3.Unusual heart rhythm (arrythmia)
4.Heart attack (cardiac arrest)

Central Nervous System Side Effects of Ritalin

5.Altered mental status (psychosis)
6.Hallucinations
7.Depression or excitement
8.Convulsions / seizures (excessive brain stimulation)
9.Drowsiness or "dopey" feeling
10.Confusion
11.Lack of sleep (insomnia)
12.Agitation, irritation, anxiety, nervousness
13.Hostility
14.Unhappiness (Dysphoria)
15.Impaired mental abilities (cognitive impairment on tests)
16.Jerky movements (Dyskinesias, tics, Tourette's syndrome)
17.Nervous habits (such as picking at skin or pulling hair)
18.Compulsive behavior
19.Depression/over-sensitivity
20.Decreased social interest
21.Zombie-like behavior

Gastrointestinal Side Effects of Ritalin

22.Eating disorders (anorexia)
23.Nausea
24.Vomiting
25.Stomach ache / cramps
26.Dry mouth
27.Constipation
28.Abnormal liver function tests

Endocrine/Metabolic Side Effects of Ritalin

29.Growth problems (pituitary dysfunction)
30.Weight loss

Other Side Effects of Ritalin

31.Blurred vision
32.Headache
33.Dizziness
34.Rash/conjunctivitis/hives
35.Hair loss
36.Inflammation of the skin (dermatitis)
37.Blood disorders (anorexia, leukoplacia)
38.Involuntary discharge of urine (enuresis)
39.Fever
40.Joint pain
41.Unusual sweating

Ritalin Withdrawal and Rebound

42.Sleep problems (insomnia)
43.Evening crash
44.Depression
45.Over-activity and irritability
46.Worsening of ADHD-like symptoms

ADHD in the UK

?In a major report from the British Psychological Society, British
physicians and psychologists are warned not to follow the Canadian and
U.S. practice of applying the label attention deficit hyperactivity
disorder (ADHD) to such a wide variety of behaviors in children.

Above all, the report urges restraint in the prescribing of
psychostimulants: "It must not be the first, and definitely not the
only, line of treatment."?

?The widespread appellation of ADHD in North America to difficult

children means that most classrooms, and many families, have children
who are so classified. Although ADHD is officially a term for a
category of mental disorder, the report said, "it has become so widely
used ... that it has a prominent place in the contemporary culture."

Yet in Britain, there is a stark difference, according to the report:
"The idea that children who don't attend or don't sit still in school
have a mental disorder is not entertained by most British clinicians."?