Thursday, October 16, 2008

Do ADHD Medications Cause Birth Defects?

ADHD Medications and Pregnancy

Due to the impulsive tendencies of adults with ADHD (currently thought to be as high as 4% of the general adult population), one would expect higher rates of unplanned pregnancies among this subgroup of the adult population. This is, in fact, often the case. As a result, it is worth investigating whether women with ADHD, who are often on medications are posing hazardous risks to their babies by taking these drugs during pregnancy. Although this area of ADHD medications and birth defects has not been studied extensively, here are some following observations and guidelines to go by:

Since some of the most common primary forms of ADHD medications are amphetamine-based stimulant drugs (such as Adderall), it is necessary to mention the fact that amphetamine usage during pregnancy has been shown to correlate with a reduction in birth weights of these children. However, other factors of growth, such as head size or birth length were unchanged, and the birth weight reduction amounts were often significantly less than a pound compared to newborns of non-users of amphetamines (or less than a 5% difference on average). Another relatively large study done primarily on the stimulant dextroamphetamine (Dexedrine), showed no significant difference in birth weights or the prevalence of birth defects.

For medications such as methylphenidate (Ritalin, Concerta), which is not an amphetamine but rather and amphetamine-like stimulant, no significant evidence has shown any connection to birth defects or lower birth weights. However, one study in which the mothers had taken methylphenidate alongside alcohol, cigarettes and other drugs showed higher rates of birth defects, mental impairments and reductions in birth sizes. However, this study had no adequate group of controls, so the effects of the ADHD drug itself could not be determined. Nevertheless, we must leave room for the possibility that this type of stimulant may worsen birth defects triggered by other maternal patterns of substance abuse.

Some other ADHD medications have not been explored in depth in human mothers, but have been investigated in other mammals. For example, in a study done on the non-stimulant ADHD medication Atomoxetine (Strattera) in pregnant rats, it was shown that weight reduction, impaired bone development, and lower offspring survival rates were tied to high levels of this drug. Of course, this was done on a different mammalian system at doses up to 30 times higher than the recommended optimal levels for humans (on a pound-for-pound basis). An even higher relative dose done on rabbits was shown to interfere with development of the circulatory system with the offspring. However, these levels were shown to be significantly over the relative toxic level of the drug in humans.

As a quick side note, I should mention that a small fraction of the population carries an uncommon form of the genetic region CYP 2D6, which, among other things, is connected to the metabolism or breakdown of the Atomoxetine drug. Individuals with this rare form (which can be determined by genetic screens), may be somewhat more at risk than their counterparts. However, individuals with this genetic form would often exhibit adverse effects to the medication early on, and would likely be placed on a different medicated treatment option.

Based on the overall dearth of information involving ADHD medications and pregnancy, we cannot arrive at any definite conclusions about their relative safety in pregnant or nursing mothers. However, if the connection between these medications and birth defects was significant, the results of some of the aforementioned studies would likely have been much more foreboding. As a result, the use of controlled and prescribed medications at appropriate doses are unlikely to pose any sort of major threat in pregnant or nursing mothers. Nevertheless, certain drugs, although much less common as primary modes of treatment for ADHD can be utilized if potential pregnancy or birth defects are a concern.

Medications such as Bupropion (Wellbutrin), have been shown to be useful in treating some forms of ADHD and may be especially effective for individuals who also suffer from depression or those who want to quit smoking. Unfortunately, one of the negative side effects of this medication is that it can increase the risk of seizures (for more information on ADHD and seizures, please check out this earlier post). Nevertheless, aside from some of these potential risks, it appears that Bupropion poses a noticeably smaller role than most stimulants in triggering birth defects.

Additionally, the drug Clonidine, which has shown to be effective in treating ADHD in several cases (especially those cases in which an ADHD comorbid disorder such as Tourette's Syndrome), is also less likely to cause birth defects than stimulants. Clonidine, which also goes by the brand names Catapres and Dixarit, is also used as a treatment for hypertension and can also be used in conjunction with stimulant medications to treat ADHD individuals. This is often done because of the sedative effects of the drug, which, when administered strategically before bedtime, can help calm things down a bit by offsetting the stimulant effects of other ADHD medications. One major caveat with Clonidine, however, is that sudden withdrawal or discontinuation of the drug can cause a rapid and dangerous spike in blood pressure. If Clonidine is to be discontinued, the individual must be gradually weaned off the drug to avoid these negative and harmful side effects.

It is my hope that some of this information will serve as good news to pregnant or soon-to-be pregnant individuals with ADHD. While the information contained here should never be a substitute for personal medical advice, I want you to leave with the fact that, at least as of now, the overall risks of birth defects or complications remain relatively low for most ADHD drugs. This is especially true when other non-prescribed chemical substances are avoided.

ADHD medications and Pregnancy