ADHD and Methylphenidate

Methylphenidate is the most common drug used in the treatment of ADHD. Prescribed under the brand name Ritalin, it is generally the first drug recommended by physicians. In addition to Ritalin, methylphenidate is sold under the brand names Methylin, Metadate, Concerta and Daytrana. Methylphenidate can also be purchased in its generic form.

Methylphenidate works by blocking roughly half of the dopamine transporters in the brain. This results in slowing the normal reuptake process, causing an increase in the amount of dopamine available for neurotransmission.Dopamine is associated with a number of functions in the brain including cognitive function, voluntary movement, motivation, punishment and reward, sleep, mood, attention, working memory and learning.¹ Using brain scan technology, Nora Volkow showed that methylphenidate increases the motivation to do math problems in healthy adults.² Furthermore, methylphenidate is fast acting, reaching peak concentration anywhere from 30 to 90 minutes after ingestion.³

Read more details about Methylphenidate.

Over the years, a number of reviews have linked the administration of methylphenidate with the reduction of hyperactivity, impulsivity and inattention in children with ADHD.⁴ The effect of methylphenidate is considered large, meaning that the rate of improvement for children taking methylphenidate is 80 percent versus 15 percent for control groups. In a four-week study of 289 children aged 7–9, methylphenidate was shown to be 77 percent effective versus 12.5 percent for control groups. Among the largest double-blind, placebo-controlled trails to date, the study also showed that the children were able to maintain their improvements during a 13-month maintenance phase.⁵

Methylphenidate is available in short-, medium- and long-acting formulas. The short-acting formulas generally work for about four hours whereas the long-acting formulas can work up to 10 hours a day. Methyphenidate also comes in a variety of preparations including tablets (both regular and chewable), solutions, capsules and the recently approved skin patch. The brand names for the different formulas are summarized here:

Short-acting:

• Ritalin
• Methylin
• Metadate

Medium-acting:

• Ritalin SR
• Methylin ER
• Metadate CD / Metadate ER

Long-acting:

• Ritalin LA
• Concerta
• Daytrana

Dosages

For children and adults, the recommended starting dose for immediate-release methylphenidate is 5 mg administered twice a day, increasing in 5 mg increments up to 20 mg per dose. A third does may be added at the clinician’s discretion. For preschoolers the recommended dose is 1.25 mg, increasing in 1.25 mg increments as needed. The dosages for medium- and long-acting formulas would be identical to the individual’s total amount of medication only taken once daily. That said, in addition to prescribing a medium- or long-acting formula, will prescribe a short-acting booster to cover the time when the medication wears off.⁶

Medical practitioners and psychiatrists

What are the precautions when taking this medicine?

All forms:

• This medicine may be habit-forming with long-term use.

• If you have been taking this medicine for several weeks, talk with healthcare provider before stopping. You may want to gradually withdraw this medicine.

• You may have certain heart tests before starting this medicine. Talk with healthcare provider.

• If you have high blood pressure, talk with healthcare provider.

• If you have mental illness, talk with healthcare provider.

• If you have PKU, talk with healthcare provider. Some products do contain phenylalanine.

• If you have seizures, talk with healthcare provider.

• Check medicines with healthcare provider. This medicine may not mix well with other medicines.

• If you are taking this medicine and have high blood pressure, talk with healthcare provider before using over-the-counter products that may increase blood pressure. These include cough or cold remedies, diet pills, stimulants, ibuprofen or like products, and certain natural products or supplements.

• Avoid alcohol (includes wine, beer, and liquor).

• Limit caffeine (for example, tea, coffee, cola) and chocolate intake. Use with this medicine may cause nervousness, shakiness, and fast heartbeat.

• Tell healthcare provider if you are pregnant or plan on getting pregnant.

• Tell healthcare provider if you are breast-feeding.

Skin patch:

• Avoid use of heat sources (such as sunlamps, tanning beds, heating pads, electric blankets, heat lamps, saunas, hot tubs, heated waterbeds). Avoid long, hot baths or sunbathing. Your temperature may rise and cause too much medicine to be released at once.

What are some possible side effects of this medicine?

• Feeling dizzy. Rise slowly over several minutes from sitting or lying position. Be careful climbing.

• High blood pressure.

• Emotional ups and downs.

• Nausea or vomiting. Small frequent meals, frequent mouth care, sucking hard, sugar-free candy, or chewing sugar-free gum may help.

• Weight loss.

• Extra muscle activity.

• Nervous and excitable.

• Not hungry.

• Inability to sleep.

• Tablet shell of Concerta™ in the stool.

• Skin irritation.

Reasons to call healthcare provider immediately

• If you suspect an overdose, call your local poison control center or emergency department immediately.

• Signs of a life-threatening reaction. These include wheezing; chest tightness; fever; itching; bad cough; blue skin color; fits; or swelling of face, lips, tongue, or throat.

• Severe behavioral problems.

• Signs or symptoms of depression, suicidal thoughts, nervousness, emotional ups and downs, abnormal thinking, anxiety, or lack of interest in life.

• Chest pain or pressure, fast heartbeat, or passing out.

• Very nervous and excitable.

• Severe skin irritation.

• Severe headache.

• Severe nausea or vomiting.

• Sudden change in vision.

• Any rash.

• No improvement in condition or feeling worse.

Dexmethylphenidate is a popular alternative to methylphenidate. Made by removing one of the side effects–causing compounds in methylphenidate, dexmethylphenidate is offered in short- and long-acting formulas under the brand name Focalin. Due to its more condensed nature, dexmethylphenidate is roughly twice as potent as methylphenidate and, thus, the recommended minimum amount is 2.5 mg. Dexmethylphenidate comes as a tablet and an extended release formula. The immediate release tablet is generally taken twice a day whereas the extended release capsule is taken just once a day. Dexmethylphenidate is used on patients who struggle with methylphenidate’s side effects.⁸

1. “Dopamine,” Wikipedia, http://en.wikipedia.org/wiki/Dopamine.
2. Nora Volkow et al. “Evidence that Methylphenidate Enhances of the Saliency of Mathematical Task by Increasing Dopamine in the Human Brain,” American Journal of Phychiatry 161, no. 7, (2004): 1173–1180.
3. Nora Volkow et al. “Mechanism of Action of Methylphenidate: Insights from PET Imaging Studies,” Journal of Attention Disorders 6 (supplement 1): S31–S43.
4. Benedetto Vitiello, “Methylphenidate in the treatment of children with attention deficit hyperactivity disorder,” Canadian Medical Association Journal 165, no. 11 (November 27, 2001).
5. Benedetto Vitiello, et al. “Methylphenidate dosage for children with ADHD over time under controlled conditions: lessons from the MTA,” *Journal of the American Academy of Child and Adolescent Psychiatry *40, (2001): 180–187.
6. Thomas E. Brown, Ph.D., Attention Deficit Disorder: The Unfocused Mind in Children and Adults, (New Haven and London: Yale University Press, 2005): 155.
7. “Methylphendiate,” Pub Med Health, July 1, 2009, http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0000606
8. Thomas E. Brown, Ph.D., Attention Deficit Disorder: The Unfocused Mind in Children and Adults, (New Haven and London: Yale University Press, 2005): 156.