Thursday, October 23, 2008

How Addictive is Ritalin?

ADHD Medications

The controversy and discussion surrounding the safety of medications for ADD and ADHD is nothing new. Among the most common criticisms of these drugs are concerns about their abuse potential and their potential risks of being habit-forming drugs. Methylphenidate (the generic name for Ritalin and Concerta), has often been mentioned in the same sentence as "cocaine", especially among the "anti-medication" and "alternative treatment" sites for ADHD treatment options. While some of these comparisons are definitely warranted, the chemical structures and modes of action of ADHD stimulants such as amphetamines and the amphetamine-like methylphenidate and the illegal street drug cocaine do bear some striking resemblances. However, it is important that we do not get lost in the hype surrounding these relationships, and instead immerse ourselves in only the facts.

In the field of organic chemistry, even minor alterations to a drug's molecular makeup can result in significant functional differences. With this in mind, however, investigation into the abuse potential of stimulant ADHD medications such as Ritalin, Concerta, Daytrana, Adderall, Dexedrine, and Focalin should be carried out in a thorough, unbiased manner. A review article from the Journal of Clinical Psychiatry on the abuse potential of the ADHD drug methylphenidate investigated key properties of the drug that play a major role in abuse potential (such as drug absorption, products produced when the drug is metabolized, and how fast the drug clears from the body). Some key findings of the article on this popular stimulant medication are summarized below:

  1. When injected, methylphenidate, cocaine, and d-amphetamine all produced similar reinforcing effects in human subjects (keep in mind that injections produce drug effects that occur much faster than those taken orally in almost all cases)
  2. Sleep deprivation boosted the reinforcing effects of methylphenidate.
  3. Methylphenidate displayed similar abuse potential to d-amphetamine for a number of studies of the general population (read "non-ADHD" population).
  4. PET scans of the brain following methylphenidate and cocaine (when both were injected) showed similar absorption rates and binding levels to their target (called the Dopamine Transporter Protein or DAT. For more more info on the DAT and ADHD, please click here). However, methylphenidate was cleared much more slowly than cocaine, which correlates to a significantly lower addiction potential for the popular ADHD drug. A quick note about this: The faster a drug is absorbed in the brain, the greater the "high" is, typically. Since injections and snorting both get the drug into the system faster than when taken orally, these methods typically lead to much greater highs and addiction potentials. Additionally, the faster this drug is then cleared, the more it is "missed" by the brain, which also results in a greater addiction potential. So for a fast-acting and fast-clearing drug, the addiction potential is typically very high. For comparison sake, methylphenidate takes about 10 minutes to enter the brain when injected (for cocaine, it is about 5 minutes), and then takes about 90 minutes to clear halfway (for cocaine it is around 20 minutes). Thus, due to its slower uptake and even slower clearance rate, methylphenidate runs a much lower risk of being habit-forming than cocaine.
  5. Oral administration of methylphenidate is much slower than this, often taking at least 1-2 hours to peak in concentration in the brain. Extended and slow-release versions of the drug (Concerta, Ritalin-SR) reduce the abuse potential even further.
  6. Individuals with ADHD are thought to have a higher amount of binding sites (DAT, see point #4) for these stimulant medications than do those without ADHD. According to the author, this makes individuals with ADHD less susceptible than the general population to habit-forming addictions surrounding the use of the stimulant methylphenidate. A more detailed explanation for this is given below:

Further explanation for Item #6 above: Although neuroscientists still disagree over the mechanism of action of both medicated and illegal stimulants, it is believed that when this DAT protein is "plugged up" or "blocked" by these stimulants, it cannot shuttle free amounts of the brain chemical dopamine into the surrounding cells. As a result, the levels of free dopamine between neuronal cells builds up. Since dopamine plays a key role in the "reward" process, it can also play a major role in both "highs" and "addictions" (both of which seek out these "rewards").

If individuals with ADHD have more of these transporter proteins to begin with, they are less likely to oversaturate all of these transporters. As a result, they are less susceptible to this dopamine buildup and the highs and addiction potentials that go along with it. In other words, individuals with ADHD can often accommodate higher levels of stimulant medications such as methylphenidate, making them less susceptible to addiction-level effects.

Based on this article and a number of other sources I have either read or followed, here is my overall take on the topic of addictions to ADHD stimulant medications:

I earnestly believe that when properly diagnosed, properly monitored by a competent physician or related professional, and by proper compliance by the medicated individual, ADHD medications are relatively safe, and the risk of developing an addiction a medication such as methylphenidate is relatively low.

Of course, as we've seen above, individuals who are not diagnosed with ADHD and take methylphenidate for recreational purposes, the potential habit-forming effects of the drug can at least approach the levels of cocaine or amphetamines. Keep in mind that the right medication at the wrong dosage can easily be just as (or even more) damaging than having the wrong medication.

Yes, stimulant drugs prescribed for ADHD are often closely related to cocaine in both chemical structure and mode of function, but the small differences between the two are sufficient enough to form a "safety barrier". Given the fact that so many undiagnosed individuals with ADHD or other related disorders often tend to "self-medicate", the dangers of "un-treatment" are just as real and just as hazardous. Keep in mind that "self-medication" is, by nature, a much more erratic form of treatment and typically abounds in negative side effects.

This is not to say that non-medication treatments should never be explored or considered as viable options for treating ADHD. Many of the so-called "alternative treatments for ADHD" are surprisingly well-grounded and increasingly-researched. However, I remain highly skeptical to those who claim that all cases of ADHD can be handled exclusively and completely by natural means. Natural remedies can be very effective for numerous cases involving ADHD, but their scope and range of applications are somewhat limited.

Please check back later for future posts related to many of these important topics on ADHD!

Tuesday, October 21, 2008

Are ADHD Stimulant Drugs Bad for your Heart?


Given the rapid rise in prescription stimulant medications for ADHD, potential concerns surrounding the side effects of these medications has been a hot topic of recent interest. News alerts like to mention the potential dangers of these drugs, and "natural health" websites are often even quicker to point out these flaws (often to the point of exaggeration).

While it is a medical fact that stimulant medications do carry certain health risks, I believe that the big question we should be asking ourselves surrounding this issue is not whether amphetamine or amphetamine-like medications are dangerous for us, but rather how can we minimize these negative effects of these substances and keep their usage as safe as possible? After all, untreated ADHD can cause enough problems in and of itself (I will describe some of these lesser known consequences in a later post).

There was a relatively recent article (2006) in the New England Journal of Medicine titled ADHD Drugs and Cardiovascular Risk sought to investigate the overall safety of these stimulant medications for treating ADHD. This article was in the Perspective section of the journal, meaning that this was an opinionated piece. We should always be careful about drawing conclusions based on opinionated sources, but I believe that the author, Steven E. Nissen of the Cardiovascular Medicine division of the Cleveland Clinic and member of the FDA Advisory Committee on ADHD drugs, makes some very important points that are at least worth mentioning.

Some of the key points of the article are summarized as follows:
  • The administration of mixed amphetamines (Adderall) and the amphetamine-like compound methylphenidate (Ritalin, Concerta) both raised systolic blood pressure (the higher number) by about 5 mm Hg. Based on other reviews, elevated blood pressure, even of this magnitude can pose as a major cardiovascular threat.
  • Taking medications of this class (called sympathomimetic agents) results in a long-term increase in heart rate at potentially dangerous levels.

  • Several drugs which are chemically similar to ADHD stimulant medications have been either pulled from the market or are subject to strong medical lobbying efforts for removal. Drugs such as ephedra and phenylpropanolamine (PPA) are both chemically similar to ADHD stimulants and have similar overlapping modes of action. Ephedra has been linked to the deaths of several professional and amateur athletes and a warning has been issued surrounding PPA and increased risks of hemorrhaging and stroke.
  • The Adverse Event Reporting System (AERS), which is a database used by the FDA to detect potential risks surrounding medications and other treatments, turned up multiple reports of sudden deaths associated with ADHD stimulant drugs, several which involved individuals with pre-existing cardiovascular defects and conditions. Additionally, a significant number of non-fatal heart difficulties such as heart attacks, irregular heart beats and stroke were observed.

  • Many of these reports were "without proper documentation", so the FDA could not make any definitive conclusions from this data. Based on this blogger's opinion, the phrase "without proper documentation" could refer to either data which is not complete to the point of being statistically significant to warrant further action, or information that was disregarded due to minor "technicalities" intrinsic to a bureacratic system. It is neither my place nor my intention to villainize the FDA, but it is important to at least consider this information and keep it tucked away in the backs of our heads.

If the information and conclusions of the article appear bleak to you, that is because they are. Nevertheless, it is important to note that this is one person's opinion, which, although echoed by many, is by no means unanimous. Having said that, I believe that the following steps should be taken for anyone considering stimulant medications for ADHD or a related disorder:

  1. A thorough screen of both an individual's background and their family history should be done before starting any type of ADHD stimulant medication.
  2. Numerical measurements such as blood pressure and heart rates should be taken frequently and passed on to the individual's physician. Keep in mind that even moderate increases in either of these can pose serious cardiovascular risks over time.
  3. For individuals with pre-existing heart problems, these medications should only be taken in cases of severe levels of ADHD (where the risks of non-treatment would be potentially more injurious to the individual than the elevated cardiovascular risks associated with these drugs).
  4. Even minor changes and symptoms need to be reported immediately and communicated to a supervising physician.

I believe that, in spite of the information presented in this, as well as other articles, ADHD medications can still be administered safely. However, I also believe that a more stringent set of conditions should be met, especially with regards to an individual's overall cardiovascular health. For those who believe that they fall into the "cardiovascular risk" category, I will soon be outlining some useful strategies to help reduce the potential risks and improve the overall safety of these ADHD medications.

Friday, October 17, 2008

ADHD Medication Recall: Dextroamphetamine Sulfate

ADHD Medications


While far from catastrophic, it is worth mentioning that there was a recent recall by some manufacturers of the ADHD stimulant medication Dextroamphetamine Sulfate. Dextroamphetamine, which also goes by the trade name Dexedrine or Dextrostat (by other manufacturers), is a relatively potent stimulant used to treat ADHD and anxiety disorders. ETHEX issued a release to the FDA on Tuesday October 15, 2008 about a recall of the 5 mg tablets of its version of the drug. Tests had shown that a sample of the medication contained oversized tablets that included a noticeably higher dosage than labeled (up to twice as high in some cases).

The good news surrounding this release is that no wholesalers or retailers of the drug have filed reports citing oversized tablets of the 5 mg of the drug (click here for a pictured link to this product). Additionally, the company manufactures 10 mg tablets of the same product, so even an accidental "double dose" (10 mg) of the medication does not exceed the dosing maximum for this particular product line. The frequency of negative side effects is often limited when total dosing is below 15 mg, and the drug typically does not result in severe reactions until around 30 mg (three times the "double dose") is taken.

Hypothetically speaking, an accidental overdose of Dextroamphetamine sulfate could cause an array of symptoms and side effects including an increased heart rate (tachycardia) and elevated blood pressure (hypertension). The risk is increased if antidepressants of the Monoamine Oxidase Inhibitor family (such as Selegiline, Zelapar capsules or transdermal Emsam patches) have been used within two weeks of the dextroamphetamine sulfate medications.

Aside from possible risks for those with current cardiovascular disorders, it is unlikely that any major side effects would occur from taking the occasional oversized capsule. Nevertheless, it raises the concern about medication dosing and how important knowledge regarding the dose-dependant effects of ADHD medications truly are. In a future post, we will explore how different doses of the same medication can often result in vastly different responses in a patient.

ADHD medications

Risperidone Boosts ADHD Stimulant Medication Effects

ADHD Medications




We often search the fine print for ADHD medication labels to see if there are potentially negative drug-drug interactions. However, an equally valid question may be: are there other medications which may boost or augment the effectiveness of an ADHD medication while keeping negative side effects to a minimum? The answer to this question appears to be "yes". We have seen in a previous post how ADHD medications and treatments can often overlap those of co-occurring disorders, such as in bedwetting. We have also seen how Atomoxetine (Strattera) can be an effective treatment option for ADHD and Tourette's. We have also explored the relative safety of ADHD stimulant medications taken during pregnancy. Now we will discuss is which medication strategies are effective for ADHD and comorbid conduct disorders and evaluate the relative safety of these medication combos.


The drug Risperidone (also referred to as Risperdal or Rispen), is a relatively new antipsychotic medication which was released in 1993 for adults and was approved in 2007 as a treatment option for both pediatric schizophrenia and pediatric bipolar disorders. A year prior to this, it was used as a potential treatment medication for pediatric autism. Given the fact that individuals with ADHD are more prone to exhibiting multiple symptoms of these disorders, Risperidone is a potential agent of interest for certain forms of ADHD.


A key study was done in 2004 by MG Aman and colleagues and was published in the Journal of Child and Adolescent Psychopharmacology, which focused on the effects of Risperidone when used in conjunction with other stimulant medications for treating ADHD in children of sub-average IQ's during a 6-week study period. Additionally, differences in behavioral disorders frequently seen alongside ADHD, such as Conduct Disorder (CD) and Oppositional Defiant Disorder (ODD) were also monitored by the study.


Although not a stimulant medication itself, the study's findings suggest that Risperidone may prove to be useful in augmenting these stimulant medications' effectiveness for these disorders or combinations of disorders. Additionally, results from the study suggest that Risperidone,by itself is often an effective treatment for hyperactivity and conduct disorders that often occur alongside ADHD. When combined with stimulants, the overall effectiveness is even greater.


Safety-wise, the study found that the use of Risperidone produced no noticeable change in the number of stimulant-related adverse drug effects. The three main ADHD stimulant medications used in the study were Methylphenidate, Pemoline, and Dextroamphetamine, with levels for each medication covering a wide dosage range. It is first important to note that while methylphenidate and dextroamphetamine are both considered to be relatively safe stimulant medications for treating ADHD, Pemoline (Cyclert) is known to be potentially harmful to the liver, and is typically used sparingly, often as a last resort among many physicians. What the study observed, however, is that risperidone, when taken alongside these stimulant medications, does not increase the number or severity of these side effects (Risperidone treatment did result in slightly more weight gain than the placebo controls, but the overall difference was small). This should be taken as good news for those concerned with the overall safety and effectiveness of combining stimulant and non-stimulant medications.


While ADHD stimulant medications and antipsychotic agents have different modes of action and different biological "targets", the results of this study suggest that the two types of medication are often able to work together and improve each other's effectiveness, while incurring minimal side effects. This suggests that for children with both ADHD and some type of oppositional or conduct disorder, prescribing Risperidone along with a stimulant medication such as Ritalin, Concerta or Dexedrine may be a highly effective and relatively safe treatment option.


ADHD medications


ADHD and Bedwetting



It's a classic problem that often puzzles parents of ADHD children. Why does my 13 year old still wet his bed? As it turns out, bed wetting, or enuresis, is a surprisingly common comorbid (co-occurring) disorder to ADHD. Other ADHD comorbid disorders that have been mentioned in previous posts include epilepsy and Tourette's Syndrome.

While there is some evidence that the two disorders share a common underlying cause (the lack of inhibitory behavior present in ADHD could span to poor muscle control), it is interesting to note that the comorbid disorder of bed wetting is connected most strongly to the Inattentive Subtype of ADHD (as opposed to the Hyperactive/Impulsive Subtype or the Combined Subtype).

Furthermore, the use of the tricyclic antidepressant drug Tofranil (Imipramine), which is often used to treat bladder control problems, has also been shown to be an effective medication for treating ADHD in some cases. We will explore this in a bit more detail in a later post, but it is important to remember that enuresis is an unusually common disorder in individuals with ADHD, especially with the Inattentive Subtype in particular. Given the fact that medications used to treat this co-occurring disorder are also sometimes useful in treating ADHD, it is my hope that other existing drugs may be further explored for their role in treating ADHD.

ADHD Medications