CNS Medications

Introduction

The central nervous system (CNS) consists of the brain and spinal cord. The brain plays a central role in the control of most bodily functions, including awareness, movements, sensations, thoughts, speech, and memory. The spinal cord carries signals between the brain and nerves in the rest of the body.

There are a number of medications which are designed to improve or repair CNS functions and many of these have been suggested as treatments for autistic people.

Those medications include anticonvulsants, antidepressants, antipsychotics, anxiolytics and hypnotics, cholinesterase inhibitors, NMDA receptor antagonists, opioid receptor antagonists, and psychostimulants

Evidence

• Most CNS medications have no effect on the core features of autism or any of the daily challenges facing autistic people. 
• Some of the newer, atypical antipsychotics like risperidone may be effective in treating some of the challenging behaviours shown by some autistic people.  
• Methylphenidate may be beneficial for the treatment of hyperactivity, impulsivity and inattention in some children and young people.

Risks and safety

Many medications contain active ingredients that can have strong effects on the mind and the body. For example, antipsychotics can cause side effects such as movement disorders, dry mouth, blurred vision, constipation, dizziness or light-headedness, and weight gain. More rarely, antipsychotics may cause more serious side effects such as changes to blood sugar levels or blood lipid levels, neuroleptic malignant syndrome (fever, faster breathing, sweating, muscle stiffness and reduced consciousness), and cardiac arrhythmia (irregular heart beat).

Anticonvulsants

Anticonvulsants (also known as antiepileptics) are a group of medications which aim to prevent or reduce the severity of fits (convulsions) in various types of epilepsy.

Some anticonvulsants are also used to treat other conditions. For example, some forms of sodium valproate are used to treat the symptoms of bipolar disorder – such as mania, impulsivity, irritability and aggression.

Anticonvulsants appear to work by regulating the amount of key neurotransmitters in the brain (especially serotonin) which reduces the amount and severity of fits.

There are a number of different anticonvulsants including lamotrigine (Lamictal), levetiracetam (Keppra), sodium valproate (Depakote) and topiramate (Topamax).

Many autistic people also have epilepsy, so they may be prescribed anticonvulsants to manage their epilepsy. Some people think that anticonvulsants could be used to reduce some of the core symptoms of autism (such as social and communication difficulties and repetitive, compulsive behaviour). 

More Information

Please see publications on Anticonvulsants

Antidepressants and Autism

Antidepressants are a group of medications which are normally used to treat people with moderate to severe depressive illness.

They may also be used to treat people with a range of other conditions including severe anxiety and panic attacks, obsessive compulsive disorders, chronic pain, eating disorders and post-traumatic stress disorder.

Antidepressants appear to work by regulating the amount of key neurotransmitters in the brain (especially noradrenaline and serotonin) which are thought to be involved with regulating mood.

The main classes of antidepressants are

• Monoamine Oxidase Inhibitors or MAOIs (which include isocarboxazid, phenelzine, selegiline and tranylcypromine).
• Selective Serotonin Reuptake Enhancers or SSREs (which include tianeptine)
• Selective Serotonin Reuptake Inhibitors or SSRIs (which include citalopram, escitalopram, fluoxetine, fluvoxamine, mirtazapine, paroxetine, and sertraline)
• Tricyclics (which include amitriptyline, amoxapine, clomipramine, dosulepin, doxepin, imipramine, lofepramine, mianserin, nortriptyline, trimipramine, and trazodone)
• Other types, such as noradrenaline re-uptake inhibitors and other drugs, such as lithium

Antidepressants are sometimes used to help autistic people with mental health problems (such as depression and anxiety), with the core features of autism (such as restricted and repetitive behaviours and interests) and with other issues (such as challenging behaviours). 

More Information

Please see

• our evaluation of Antidepressants
• Publications on Antidepressants

Antipsychotics

Antipsychotics  (also known as neuroleptics or major tranquillisers) are a group of medications used to help people with some mental health problems — mainly schizophrenia and bipolar affective disorder. They can also be used to help people with severe anxiety or depression.

There are two main types of antipsychotics.

1. the older, typical or conventional antipsychotics, which include haloperidol, chlorpromazine, fluphenazine, molindone, piperidinephenthiazine, trifluoperazine, thiothixene, and trifluperidol.

2. the newer, atypical antipsychotics which include aripiprazole (Abilify), clozapine (Clozaril), olanzapine (Zolafren), pimozide (Orap), quetiapine (Seroquel), and risperidone (Risperdal).

Antipsychotics appear to work by changing the amounts and the effects of different neurotransmitters (chemicals in the brain).  Traditional antipsychotics work mainly by reducing the amount and the action of dopamine. Atypical antipsychotics work mainly by changing the amount and the action of a range of neurotransmitters including dopamine, serotonin, noradrenaline and acetylcholine.

Some people believe that antipsychotics can also be used to treat some of the more challenging problems faced by autistic individuals including aggression, irritability, hyperactivity, self injury, and stereotyped behaviour.

More Information

Please see 

• our evaluation of Antipsychotics
• our evaluation of Aripiprazole
• our evaluation of Olanzapine
• our evaluation of Risperidone
• publications on antipsychotics

Anxiolytics and Hypnotics

Anxiolytics (also known as anti-anxiety agents or minor tranquillisers) are a group of medications used to treat feelings of anxiety or nervousness.

Hynoptics (also known as sleeping pills or sedatives) are drugs used to treat sleeplessness.

Benzodiazepines are the most commonly used anxiolytics and hypnotics as they have fewer side effects than other anxiolytics and hypnotics such as barbiturates. 

Benzodiazepines are believed to work by modifying the amount and action of the neurotransmitter gamma-aminobutyric acid (GABA).

Benzodiazepines include diazepam (Valium); buspirone (BuSpar); and lorazepam (Ativan).

Anxiolytics and hypnotics are sometimes used to treat autistic people who suffer from anxiety, nervousness, sleeplessness or other problems.

More Information

Please see publications on Anxiolytics

Cholinesterase Inhibitors

Cholinesterase inhibitors, also known as acetylcholinesterase inhibitors, are a group of medications used to treat conditions such as Alzheimer's disease.

Cholinesterase inhibitors are believed to improve some mental functions by increasing the amount of acetylcholine in the brain. Increased concentrations of acetylcholine lead to increase communication between nerve cells.

There are a number of different types of cholinesterase inhibitors including donepezil (Aricept); galantamine (Reminyl); rivastigmine (Exelon); and tacrine (Cognex).

Some people believe that cholinesterase inhibitors can also be used to treat attention deficit hyperactivity disorders in autistic people.

More Information

Please see publications on Cholinesterase Inhibitors.  

NMDA Receptor Antagonists

NMDA receptor antagonists are a group of medications often used in the treatment of neurological conditions such as Alzheimer's desease, Parkinson's diseasse or amyotrophic lateral sclerosis. 

NMDA receptor antagonists are a class of drugs that work to antagonise (inhibit) the action of the the N-methyl d-aspartate receptor (NMDAR).

NMDAR is a neurotransmitter which decreases the effect of other chemicals in the brain including another neurotransmitter, glutamate. Too much glutamate can damage nerve cells responsible for learning and memory.

There are a number of different types of NMDA receptor antagonists including amantadine (Symmetrel) and memantine (Namenda).

Some people believe that NMDA receptor antagonists can also be used to treat the core features of autism including difficulties with social communication and social interaction, and restricted and repetitive behaviours and interests. 

More information

Please see publications on NMDA receptor antagonists

Opioid Receptor Antagonists

Opioid receptor antagonists are a group of medications used to treat conditions such as alcohol dependence, opioid dependence and opioid overdose.

Opioid receptor antagonists are morphine-like substances which can be used to block the effect of endorphins in our central nervous system. Endorphins are the substances in our bodies which produce 'highs' in mood, such as when we exercise vigorously.

There are several types of opioid receptor antagonists

• Naltrexone (Adepen) is an opioid receptor antagonist used to treat conditions such as alcohol dependence and opioid dependence.
• Naloxone (Narcan) is an opioid receptor antagonist used to counter the effects of opioid overdose.

Some people believe that naltrexone can be used with some autistic people to reduce challenging behaviours such as self injury, hyperactivity and ritualistic behaviour.

More Information

Please see publications on Opioid Antagonists

Psychostimulants and Related Medications

Psychostimulant medications (or central nervous system stimulants) are a group of medications used to treat conditions such as ADHD, hyperkinetic disorder and narcolepsy.

There are several other types of other medications, such as selective noradrenaline reuptake inhibitors (SNRIs), which are also used to treat these conditions and are therefore grouped with them.

Psychotimulant medications are believed to work by increasing the amount of dopamine and noradrenaline (neurotransmitters) in the brain.  SNRIs are believed to work by increasing the amount of serotonin and noradrenaline in the brain. Increasing the amount of these neurotransmitters is believed to improve self-control, attention and concentration.

• There are two main types of psychostimulant medication: dextroamphetamine (Dexedrine) and methylphenidate (Ritalin). 
• There are several types of  selective noradrenaline reuptake inhibitors including atomoxetine (Strattera).

Some people think that these medications can be used with some autistic people to reduce problem behaviours, such as inattention, distractibility, hyperactivity, and impulsivity.

More Information

Please see

• our evaluation of Methylphenidate
• publications on Methylphenidate
• publications on Atomoxetine
• publications on Psychostimulant Medications
• publications on Selective Noradrenaline Re-Uptake Inhibitors

Related Pages

• Medications
• Types of Intervention
• Interventions

Updated

27 May 2022