A Controlled Trial of Herbal Treatment for ADHD

Many par­ents, health care pro­fes­sion­als, and edu­ca­tors agree that there is a press­ing need to devel­op effec­tive treat­ments for ADHD to com­ple­ment or sub­sti­tute for tra­di­tion­al med­ica­tion and behav­ior ther­a­py approach­es. This is because such treat­ments do not work for every­one, impor­tant dif­fi­cul­ties often remain even when these treat­ments are effec­tive, and evi­dence for the long-term ben­e­fits of these treat­ments remains less com­pelling than one would like. In addi­tion, in the case of med­ica­tion treat­ment, some indi­vid­u­als expe­ri­ence intol­er­a­ble side effects and many have con­cerns about tak­ing ADHD med­ica­tion for an extend­ed period.

One alter­na­tive approach to treat­ing ADHD has relied on the use of Com­pound Herbal Prepa­ra­tions (CHP) derived from tra­di­tion­al Chi­nese med­i­cine. Prac­ti­tion­ers of this approach believe that such prepa­ra­tions have impor­tant cog­ni­tive enhanc­ing prop­er­ties because they sup­ply essen­tial nutri­ents, fat­ty acids, phos­pho­lipids, amino acids, B vit­a­mins, min­er­als, and oth­er micronu­tri­ents that are impor­tant for opti­mal brain growth and devel­op­ment. As a treat­ment for ADHD, the idea is that many indi­vid­u­als with ADHD have defi­cien­cies in essen­tial nutri­ents that com­pro­mise healthy brain devel­op­ment and result in ADHD symp­toms. Pro­vid­ing these nutri­ents via an appro­pri­ate­ly pre­pared herbal com­pound thus has the poten­tial to be ther­a­peu­tic and reduce these symptoms.

This idea was test­ed recent­ly in a ran­dom­ized-con­trolled tri­al of a spe­cif­ic CHP for chil­dren with ADHD [Katz, Kol-Degani, & Kav-Vena­ki (2010). A com­pound herbal prepa­ra­tion (CHP) in the treat­ment of ADHD: A ran­dom­ized con­trolled tri­al. Jour­nal of Atten­tion Dis­or­ders. Pub­lished online on March 12, 2010.] Par­tic­i­pants were 120 6–12 year-old chil­dren new­ly diag­nosed with ADHD based on a com­pre­hen­sive diag­nos­tic eval­u­a­tion. These chil­dren were all eval­u­at­ed at the She­ba Med­ical Cen­ter, one of the largest uni­ver­si­ty-affil­i­at­ed ter­tiary care cen­ters in Israel.

(Editor´s note: Dr. David Rabin­er, author of this arti­cle, pre­vi­ous­ly reviewed a 2005 meta-analy­sis whose find­ings need to be kept in mind to con­tex­tu­al­ize this new study. In the arti­cle Dietary Inter­ven­tion for ADHD: A Meta-Analy­sis, Dr. Rabin­er con­clud­ed that “Results from this meta-analy­sis pro­vide strong evi­dence that the behav­ior of chil­dren with ADHD can be made worse by dietary fac­tors, and that elim­i­nat­ing AFCs from their diets will, on aver­age, result in behav­ioral improve­ments. This result is con­sis­tent with with accu­mu­lat­ing evi­dence that neu­robe­hav­ioral tox­i­c­i­ty may result from a wide vari­ety of dis­trib­uted chemicals.”)

Chil­dren were ran­dom­ly assigned to receive either the CHP (n=80) or a place­bo (n=40) that was spe­cial­ly pre­pared to taste, smell, and look sim­i­lar to the herbal for­mu­la. Ran­dom­iza­tion was done in a 2:1 ratio because the treat­ment was to last 4 months, and inves­ti­ga­tors wished to min­i­mize the num­ber of chil­dren who would receive place­bo treat­ment for which no ben­e­fit was anticipated.

Active ingre­di­ents in the CHP — brand name Nur­ture & Clar­i­ty — includ­ed Paeo­ni­ae Alba, With­a­nia Som­nifera, Cen­tel­la Asi­at­i­ca, Spir­uli­na Platen­sis, Baco­pa Monieri, and Mel­lis­sa Offic­i­nalis. All raw herbs used in the prepar­ing the com­pound were approved by the Israeli Min­istry of Health as safe, food-grade herbs.

Nei­ther par­ents, chil­dren, research assis­tants who test­ed the chil­dren or staff mem­bers who dis­trib­uted the appro­pri­ate for­mu­la to par­tic­i­pants knew who received the CHP and who was giv­en the place­bo. To con­firm that the place­bo prepa­ra­tion could not be dis­tin­guished from the CHP, 20 Israeli med­ical stu­dents were pro­vid­ed with both prepa­ra­tions and asked which was which; these stu­dents were unable to reli­ably tell them apart. Based on the infor­ma­tion pro­vid­ed, there­fore, this appears to have been a care­ful­ly con­duct­ed tri­al with strong ran­dom­iza­tion and blind­ing procedures.

Pri­or to begin­ning treat­ment with the CHP or place­bo, chil­dren were admin­is­tered the Test of Vari­ables of Atten­tion (TOVA), a wide­ly used com­put­er­ized test of atten­tion and impul­siv­i­ty. In the TOVA, chil­dren sit in front of a com­put­er and are instruct­ed to respond using a par­tic­u­lar key when­ev­er a des­ig­nat­ed stim­u­lus appears. When any oth­er stim­u­lus flash­es they are not sup­posed to respond. The test lasts for over 20 min­utes and good per­for­mance requires the child to sus­tain atten­tion to an unin­ter­est­ing task for a rea­son­ably long peri­od of time.

Fail­ing respond when a response is required — errors of omis­sion — are believed to reflect prob­lems with sus­tain­ing atten­tion. Respond­ing when the wrong stim­u­lus appears — errors of com­mis­sion — reflect impul­sive respond­ing. Oth­er mea­sures from the TOVA include response reac­tion time and reac­tion time vari­abil­i­ty. Chil­dren receive a score on each scale that com­pares their per­for­mance to age-matched peers from a large nor­ma­tive sam­ple. They are also assigned an over­all score, again based on age appro­pri­ate norms.

Fol­low­ing base­line admin­is­tra­tion of the TOVA, chil­dren were treat­ed with the CHP or place­bo prepa­ra­tion over a 4‑month peri­od. At the end of 4 months the TOVA was admin­is­tered a sec­ond time. This enabled the researchers to deter­mine whether chil­dren receiv­ing the CHP demon­strat­ed sig­nif­i­cant improve­ment on the test com­pared to those who received placebo.

- Results -

At the fol­low-up assess­ment, data was obtained on 73 of 80 chil­dren who received the CHP com­pared to only 19 of 40 who received place­bo. The sig­nif­i­cant­ly greater drop-out rate among place­bo-treat­ed chil­dren reflect­ed the greater num­ber of par­ents who were not sat­is­fied with their child’s response and who with­drew to pur­sue oth­er options.

Results from the TOVA were ana­lyzed in 2 pri­ma­ry ways. First, with­in each group, researchers test­ed whether there was sig­nif­i­cant improve­ment from pre-test to post-test. Then, they direct­ly com­pared CHP vs. place­bo dif­fer­ences con­trol­ling for age and sex. Because pre­lim­i­nary analy­ses indi­cat­ed that results were con­sis­tent across dif­fer­ent ADHD sub­types, i.e., inat­ten­tive, hyper­ac­tive-impul­sive, and com­bined, chil­dren with each sub­type were com­bined in all analyses.

For the with­in group analy­ses, chil­dren in the CHP group showed sta­tis­ti­cal­ly sig­nif­i­cant improve­ment on all indices of the TOVA. In fact, their aver­age fell well with­in the nor­mal range on all TOVA vari­ables. In con­trast, those in the place­bo group showed small declines on each TOVA vari­able and con­tin­ued to per­form in the below aver­age range.

A direct com­par­i­son of the two groups yield­ed equal­ly strong results, as CHP- treat­ed chil­dren made sig­nif­i­cant­ly greater improve­ment than place­bo-treat­ed chil­dren on every TOVA scale. The mag­ni­tude of these group dif­fer­ences would be con­sid­ered large.

The authors con­duct­ed a final analy­sis in which they assumed that all con­trol chil­dren who with­drew would have improved as much as the aver­age child in the CHP group had they con­tin­ued and that all CHP chil­dren who with­drew would not have improved at all. Even when these con­ser­v­a­tive assump­tions were made, chil­dren in the CHP group were still per­form­ing sig­nif­i­cant­ly bet­ter on average.

It should also be not­ed that care­ful assess­ments were con­duct­ed dur­ing the 4‑month tri­al on the safe­ty and tol­er­a­bil­i­ty of the CHP. No seri­ous adverse effects were report­ed and the rate of even mild adverse events among CHP-treat­ed chil­dren was actu­al­ly low­er than for chil­dren who received placebo.

- Sum­ma­ry and Implications -

Results from this ran­dom­ized-con­trolled tri­al of a com­pound herbal treat­ment for ADHD clear­ly indi­cate sig­nif­i­cant improve­ment on an objec­tive mea­sure of sus­tained atten­tion and impul­sive respond­ing, i.e., the TOVA. Giv­en how care­ful­ly the tri­al was con­duct­ed, and the mag­ni­tude of the effects that were found, this is an encour­ag­ing and impres­sive result. Beyond the TOVA results, the fact that over 90% of par­ents kept their child on the herbal com­pound over 4 months — com­pared to under 50% of chil­dren receiv­ing place­bo — sug­gests that they were observ­ing real-world ben­e­fits in their child and were not receiv­ing pres­sure from teach­ers to ‘do some­thing’. Clear­ly, these find­ings under­score the poten­tial ben­e­fits of this herbal com­pound in the treat­ment of ADHD.

Despite these impres­sive results, how­ev­er, there remain sev­er­al impor­tant rea­sons for cau­tion regard­ing the poten­tial ben­e­fits of this treat­ment. First, this is only a sin­gle study and repli­ca­tion with anoth­er sam­ple would be impor­tant for increas­ing con­fi­dence in the find­ings. The need for repli­cat­ing treat­ment effects is impor­tant for any treat­ment approach and hope­ful­ly such work is already underway.

Sec­ond, and I believe this is espe­cial­ly impor­tant, the out­come mea­sures used to eval­u­ate treat­ment impact were unfor­tu­nate­ly lim­it­ed. While the TOVA cer­tain­ly offers objec­tive evi­dence of improved atten­tion and reduced impul­sive respond­ing, the mea­sure­ment bat­tery would have ide­al­ly includ­ed behav­ior rat­ings made by par­ents and teach­ers. Such rat­ings would pro­vide a clear­er indi­ca­tion than the TOVA results of whether treat­ment yield­ed reduc­tions in ADHD symp­toms that were observed at home and at school, which are the out­comes that real­ly mat­ter. Although the fact that most par­ents kept their child on the herbal com­pound for the 4 months sug­gests that ‘real-world’ reduc­tions in ADHD symp­toms were evi­dent, col­lect­ing the stan­dard­ized behav­ior rat­ings is nec­es­sary to con­firm this.

Final­ly, the study pro­vides no real infor­ma­tion on how long any ben­e­fits of this treat­ment would be sus­tained. Is this com­pound some­thing chil­dren need to take indef­i­nite­ly — as is often true for med­ica­tion — or do the ben­e­fits per­sist even after the com­pound is no longer admin­is­tered? This would be impor­tant infor­ma­tion to col­lect in sub­se­quent work.

These lim­i­ta­tions not with­stand­ing, this is an inter­est­ing and impor­tant study that high­lights the need for addi­tion­al research on this promis­ing inter­ven­tion approach for chil­dren with ADHD.

– Dr. David Rabin­er is a child clin­i­cal psy­chol­o­gist and Direc­tor of Under­grad­u­ate Stud­ies in the Depart­ment of Psy­chol­ogy and Neu­ro­science at Duke Uni­ver­sity. He pub­lishes Atten­tion Research Update, an online newslet­ter that helps par­ents, pro­fes­sion­als, and edu­ca­tors keep up with the lat­est research on ADHD, and teach­es the online course  How to Nav­i­gate Con­ven­tion­al and Com­ple­men­tary ADHD Treat­ments for Healthy Brain Devel­op­ment.

Relat­ed articles:

• Dietary Inter­ven­tion for ADHD: A Meta-Analysis
• Nutri­tion and sup­ple­ments (DHEA, Gink­go Bilo­ba, Omega‑3): sep­a­rat­ing myth from fact