This category includes all prescription and non-prescription drugs that are intended to treat, prevent, or alleviate any physical or psychological symptoms commonly experienced by children with ASD. The medications used for ASD aren’t usually intended to correct the underlying neurological or developmental abnormalities, but instead are directed to help the difficulties that result from these changes. Currently, no one knows for sure how many children with ASDs are taking medications, but rough estimates are around 50%. Medications are often a key component to the overall treatment strategy for a child on the spectrum. In general, compared to other treatment categories, medications have the most evidence supporting their use, although the bulk of research about each one has usually been for some other disorder.
Once available on the US market, medications generally follow a predictable, but often slow path, in being approved (or rejected) for use in children with an ASD. This path progresses from a small number of clinical observations with positive outcomes (often incidental), then publication of a few case studies, followed by increased off-label use of the drug, then open-label drug trials, and then ultimately undergoing the gold standard of scientific proof---the placebo-controlled, randomized controlled trial.
Targeting the Brain...
Many types of medications are being used. The most common and widely accepted drugs target the brain and are intended to help manage neurological problems---such as seizures, mood disturbances, and behavioral issues. The medications used most often in autism can generally be placed in one of the following groups: 1
Antipsychotic drugs: These drugs are commonly used to treat psychotic symptoms experienced by individuals with schizophrenia, bipolar disorder, depression and other mental health disorders. Psychotic symptoms include hallucinations (seeing or hearing things that aren’t really there) and delusions (irrational thoughts and fears). In ASDs, some of the newer antipsychotics (known as “atypical antipsychotics”) are used to treat irritability and behavioral problems, such as aggression, self-injury, and rapid mood swings.
The "atypical antipsychotics," named such because they have fewer unwanted side effects compared to typical antispychotics, are widely used to treat individuals with ASD. Of the newer medications, risperidone (Risperdal™) is the best studied and most frequently prescribed for ASD. Primarily used for the treatment of conditions such as bipolar disorder and schizophrenia, risperidone primarily acts by blocking dopamine receptors in the brain. Dopamine receptors are involved in movement, cognition, and mood. Risperidone may also affect other chemical pathways in the brain such as serotonin (also related to behavior and mood) which is known to be abnormal in some individuals with ASD. 2 First reportedly used for ASD in the mid-90s, risperidone was formally approved by the US Food and Drug Administration (FDA) in October 2006 for treatment of some ASD-related symptoms in children and adolescents. Specifically, risperidone was approved for irritability evidenced by behaviors such as aggression, self-injury, temper tantrums, and rapid mood changes. Recent studies suggest that treatment with risperidone may have a more generalized use in children with ASD, producing global improvements in functioning and social responsiveness. 3 The main side effects associated with risperidone are sleepiness and weight gain.
- Additional atypical antipsychotics used in autism: clozapine (Clozaril™), olanzapine (Zyprexa™), quetiapine (Seroquel™), ziprasidone (Geodon™)
- Other antipsychotics commonly used in autism include: haloperidol (Haldol™), chlorpromazine (Thorazine™), apriprazole (Abilify™)
Antidepressants: These drugs are used primarily to treat depressive disorders but many are also effective treatment for anxiety disorders, including Obsessive Compulsive Disorder. They are also used to treat ADHD, bedwetting and smoking cessation. Most antidepressants work by changing the levels of specific chemicals in the brain called neurotransmitters. There are four main categories of antidrepressants: monoamine oxidase (MAO) inhibitors, tricyclic antidepressants (TCAs), selective serotonin reuptake inhibitors (SSRIs) and “other agents.”
The TCAs and SSRIs have been the most studied in autism, but results have not been clearly beneficial and some of the drugs were associated with considerable side effects. Other agents, such as venlafaxine (Effexor), have also undergone investigation for possible use in children with autism, but again produced similar mixed results. Despite the lack of definitive results, many different antidepressants are being used by children with ASD. Some of the symptoms being targeted by these drugs include aggression, self-injurious behavior, anxiety, agitation, overactivity, and some stereotypic behaviors. 4
- SSRIs used in autism: fluvoxamine (Luvox™, Faverin™), fluoxetine (Prozac™, Fontex™, Seromex™, Seronil™, Sarafem™), Sertraline (Zoloft™, Lustral™, Serlain™), Paroxetine (Paxil™, Seroxat™, Aropax™, Deroxat™, Paroxat™), Citalopram (Celexa™, Cipramil™, Emocal™, Sepram™, Seropram™), Escitalopram (Lexapro™, Cipralex™, Esertia™)
- TCAs used in autism: clomipramine (Anafranil™), desipramine (Norpramine™), amitriptyline (Elavil™, Endep™),imipramine (Tofranil™)
- Other antidepressants used in autism include: venlafaxine (Effexor™)
Stimulants: These drugs are primarily used to treat Attention Deficit Hyperactivity Disorder (ADHD). Many children with ASD have similar symptoms of inattention, overactivity, and impulsivity and thus stimulant medications are commonly used. These drugs are available in short-acting and long-acting formulas. How central nervous system (CNS) stimulants work is not completely understood, but the medication is thought to target the brainstem arousal system and the cortex.
- Methylphenidate (Ritalin™) is the most studied and most commonly used psychostimulant. Most of the published studies involving children with autism have been small sets of case-reports with mixed outcomes. However, a recent double-blind, placebo-controlled study conducted by the Research Units on Pediatric Psychopharmacology (RUPP) Autism Network (Posey et al., 2004) confirmed earlier findings that about half (49%) of children with autism responded to methylphenidate with decreased hyperactivity and inattention. This response rate is significantly lower than the response of children with a diagnosis of ADHD that do not have autism. In addition, a large percentage (18%) of the children with autism treated with methylphenidate experienced significant side effects that were intolerable. To sum it all up, some children with autism will benefit from the use of psychostimulants and be able tolerate the side effects. At this point, it is not possible to identify this group of kids without actually trying the medication. 5
- Other psychostimulants used in children with autism: amphetamine mixed salts (Adderall™, Adderall XR™), methylphenidate XR (Concerta™, Metadate CD™), dextroamphetamine (Dexedrine™)
Mood Stabilizers: This group of drugs is mostly used to treat bipolar disorder in both children and adults. Other uses also include behavioral symptoms such as aggression, self-injury, impulsivity and conduct disorder. Many anti-seizure medications have mood-stabilizing properties as well. Only a handful of these drugs have been studied in children with autism and definitive, reproducible results are not available. Most of these medications are not commonly used for mood stabilization or behavioral symptoms in children with ASD but are occasionally tried on a case-by-case basis. Those that are effective anti-seizure medications are used for that purpose in children with ASD who also have seizures (see Anticonvulsants).
- Mood stabilizers possibly used in autism: lithium, lamotrigine (Lamictal™), valproic acid (Depakene™, Depakote™), carbamazepine (Tegretol™), topiramate (Topamax™), oxcarbazepine (Trileptal™), and levetiracetam (Keppra™)
Anticonvulsants: This group of drugs is used to treat seizures which occur in as many as one-third of children with an ASD. In general the treatment of seizures in children with autism is the same as the treatment of seizures in other children. Very few studies have been conducted or reported on the effects of anticonvulsants on children with ASD. Despite the lack of specific evidence, anticonvulsants are prescribed routinely for children with ASD and seizures. The side effects for children with autism are thought to be the same as for other children receiving anticonvulsant medications. 6
- Anticonvulsants used in children with autism: phenytoin (Dilantin™), clonazepam (Klonopin™), carbamazepine (Tegretal™), valproic acid (Depakote™, Depakene™)
Other: Many other medications targeting the central nervous system are being used for children with ASD. The following drugs are just a partial list of other CNS medications being used in autism. 7
- Other medications with CNS effects used in ASD: alprazolam (Xanax™, Niravam™), buspirone (Buspar™), lorazepam (Ativan™) , naltrexone (Vivitrol™), diazepam (Valium™), melatonin, antihistamines
But Not Just the Brain…
The brain is an easily agreed upon target for medications in the treatment of ASD. Other body systems are also being targeted by drug therapy although not all clinicians or care providers agree on how these additional problems relate to ASD. Is there an underlying explanation for all the problems? Do the neurological abnormalities associated with ASD result in other problems? Or perhaps, the diverse group of signs and symptoms are not related at all? For the most part, the answers remain unknown. Currently, specific focus has been placed on the gastrointestinal tract as well as the immune system of children with ASD.
Gastrointestinal agents: The gastrointestinal (GI) tract is just one of the body systems identified as problematic in children with ASDs and thus is specifically targeted by medications in some cases. Medications are generally selected based on their efficacy for a particular symptom like chronic diarrhea, constipation, or acid reflux disease. The effect, if any, these drugs have on a child’s overall level of functioning is unclear.
- Secretin, a gastrointestinal agent produced naturally in the intestines, is one of the best studied, but now disproven, medical therapies for the treatment of autism. First reported as having a positive effect on autism-related behaviors in 1998, secretin was studied in over 14 randomized controlled trials over the ensuing 5 years. Ultimately, the scientific community concluded that there was no evidence that secretin was an effective therapy for ASD.8
- Other GI medications reportedly used in children with ASD: probiotics, famotidine (Pepcid™), bethanechol (Bethanechol™, Urecholine™)
- For information about other GI-related interventions: refer to the sections on Vitamins and Supplements and Special Diets.
Immunological agents: The connection between the immune system and ASDs is under active investigation. It has been reported that children with ASDs are more likely to have infectious and allergy-related disorders (including more frequent ear infections and food allergies). In addition, many abnormalities have been reported in laboratory values that are related to the functioning of the immune system. Therefore, medications that alter the immune system are actively being used in children with autism. 9
- Immunologic therapies used in children with ASD: intravenous immunoglobulins (IVIG), anti-viral medications, anti-fungal medications, and steroid therapy