Treatment for MSS is symptomatic and supportive including physical and occupational therapy, speech therapy, and special education. Cataracts must be removed when vision is impaired, generally in the first decade of life. Hormone replacement therapy is needed if hypogonadism is present.

There is no cure for PMD, nor is there a standard course of treatment. Treatment, which is symptomatic and supportive, may include medication for seizures and spasticity. Regular evaluations by physical medicine and rehabilitation, orthopedic, developmental and neurologic specialists should be made to ensure optimal therapy and educational resources. The prognosis for those with Pelizaeus–Merzbacher disease is highly variable, with children with the most severe form (so-called connatal) usually not surviving to adolescence, but survival into the sixth or even seventh decades is possible, especially with attentive care. Genetic counseling should be provided to the family of a child with PMD.

In December 2008, StemCells Inc., a biotech company in Palo Alto, received clearance from the U.S. Food and Drug Administration (FDA) to conduct Phase I clinical trials in PMD to assess the safety of transplanting human neural stem cells as a potential treatment for PMD. The trial was initiated in November 2009 at the University of California, San Francisco (UCSF) Children's Hospital.

Treatments are usually based on the individuals symptoms that are displayed. The seizures are controlled with anticonvulsant medication. For the behavior problems, the doctors proscribe to a few medications and behavioral modification routines that involve therapists and other types of therapy. Even if mental retardation is severe, it does not seem to shorten the lifespan of the patient or to get worse with age.

There is no known cure available for the Wilson-Turner Syndrome. Instead, treatment options are available to fight individual symptoms. For obesity, a nutritional diet manipulation is combined with an exercise regimen that has a greater energy expenditure than intake. For hypogonadism, testosterone replacement is done. Finally, for gynecomastia, weight loss using similar methods for obesity is prescribed. However, if the individual finds his increased breast tissue psychologically distressing and/or is too severe, reduction mammaplasty is done. Currently, researchers are investigating therapy using antiestrogens and aromatase inhibitors to treat persistent pubertal gynecomastia.

Treatment is supportive.

- The aplastic anemia and immunodeficiency can be treated by bone marrow transplantation.

- Supportive treatment for gastrointestinal complications and infections.

- Genetic counselling.

The treatment of 2-Hydroxyglutaric aciduria is based on seizure control, the prognosis depends on how severe the condition is.

No specific treatment is known that would prevent, slow, or reverse HSP. Available therapies mainly consist of symptomatic medical management and promoting physical and emotional well-being. Therapeutics offered to HSP patients include:

- Baclofen – a voluntary muscle relaxant to relax muscles and reduce tone. This can be administered orally or intrathecally. (Studies in HSP )

- Tizanidine – to treat nocturnal or intermittent spasms (studies available )

- Diazepam and clonazepam – to decrease intensity of spasms

- Oxybutynin chloride – an involuntary muscle relaxant and spasmolytic agent, used to reduce spasticity of the bladder in patients with bladder control problems

- Tolterodine tartate – an involuntary muscle relaxant and spasmolytic agent, used to reduce spasticity of the bladder in patients with bladder control problems

- Botulinum toxin – to reduce muscle overactivity (existing studies for HSP patients)

- Antidepressants (such as selective serotonin re-uptake inhibitors, tricyclic antidepressants and monoamine oxidase inhibitors) – for patients experiencing clinical depression

- Physical therapy – to restore and maintain the ability to move; to reduce muscle tone; to maintain or improve range of motion and mobility; to increase strength and coordination; to prevent complications, such as frozen joints, contractures, or bedsores.

Treatment for individuals with Dandy–Walker Syndrome generally consists of treating the associated problems, if needed.

A special tube (shunt) to reduce intracranial pressure may be placed inside the skull to control swelling. Endoscopic third ventriculostomy is also an option.

Treatment may also consist of various therapies such as occupational therapy, physiotherapy, speech therapy or specialized education. Services of a teacher of students with blindness/visual impairment may be helpful if the eyes are affected.

Response to treatment is variable and the long-term and functional outcome is unknown. To provide a basis for improving the understanding of the epidemiology, genotype/phenotype correlation and outcome of these diseases their impact on the quality of life of patients, and for evaluating diagnostic and therapeutic strategies a patient registry was established by the noncommercial International Working Group on Neurotransmitter Related Disorders (iNTD).

There is no cure for Machado-Joseph Disease. However, treatments are available for some symptoms. For example, spasticity can be reduced with antispasmodic drugs, such as baclofen. The Parkinsonian symptoms can be treated with levodopa therapy. Prism glasses can reduce diplopic symptoms. Physiotherapy/Physical Therapy and/or occupational therapy can help patients by prescribing mobility aids to increase the patients' independence, providing gait training, and prescribing exercises to maintain the mobility of various joints and general health to decrease the likelihood of falls or injuries as a result of falls. Walkers and wheelchairs can greatly help the patient with everyday tasks. Some patients will experience difficulties with speech and swallowing, therefore a Speech-Language Pathologist can assist the patients to improve their communicating abilities and their issues with swallowing.

Unlike Borjeson-Forssman-Lehmann syndrome, a disorder that was determined to be very similar to WTS, the individuals with Wilson–Turner syndrome do not develop cataracts or hypermetropia later in life. By far, the most debilitating part of this disorder is intellectual disability. Many of the other symptoms are more easily managed through hormone treatment, proper diet and exercise, and speech therapy.

Treatment for individuals with PLS is symptomatic. Baclofen and tizanidine may reduce spasticity. Quinine or phenytoin may decrease cramps. Some patients who do not receive adequate relief from oral treatment may consider intrathecal baclofen (i.e., infusion of medication directly into the cerebrospinal fluid via a surgically placed continuous infusion pump). However, patients are carefully selected for this type of procedure to ensure that they will likely benefit from this invasive procedure.

Physical therapy often helps prevent joint immobility. Speech therapy may be useful for those with involvement of the facial muscles. Physiotherapy treatment focuses on reducing muscle tone, maintaining or improving range of motion, increasing strength and coordination, and improving functional mobility. In PLS, stretching is thought to improve flexibility and can also reduce muscle spasticity and cramps.

Patients with PLS may find it beneficial to have an evaluation, as well as follow-up visits at multidisciplinary clinics, similar to those available for people with ALS. These multidisciplinary clinics may provide patients with the necessary treatment that they require by having an occupational therapist, physical therapist, speech language pathologist, dietician and nutritionist, all in one site.

Because pachygyria is a structural defect no treatments are currently available other than symptomatic treatments, especially for associated seizures. Another common treatment is a gastrostomy (insertion of a feeding tube) to reduce possible poor nutrition and repeated aspiration pneumonia.

As a matter of everyday maintenance, muscle stretching, range of motion exercises, yoga, contact improvisation, modern dance, resistance training, and other physical activity regimens are often utilized by those with spastic CP to help prevent contractures and reduce the severity of symptoms.

Major clinical treatments for spastic diplegia are:

- Baclofen (and its derivatives), a gamma amino butyric acid (GABA) substitute in oral (pill-based) or intrathecal form. Baclofen is essentially chemically identical to the GABA that the damaged, over-firing nerves cannot absorb, except that it has an extra chemical 'marker' on it that makes the damaged nerves 'think' it is a different compound, and thus those nerves will absorb it. Baclofen is noted for being the sole medication available for GABA-deficiency-based spasticity which acts on the actual cause of the spasticity rather than simply reducing symptomatology as muscle relaxants and painkillers do. The intrathecal solution is a liquid injected into the spinal fluid for trial, and if successful in reducing spasticity, thereafter administered via an intrathecal pump, which has variously been proven potentially very dangerous on one or another level with long-term use (see article), including sudden and potentially lethal baclofen overdose, whereas the oral route, which comes in 10- or 20-milligram tablets and the dosage of which can be gently titrated either upward or downward, as well as safely ceased entirely, has not.

- Antispasmodic muscle relaxant chemicals such as tizanidine and botulinum toxin (Botox), injected directly into the spastic muscles; Botox wears off every three months.

- Phenol and similar chemical 'nerve deadeners', injected selectively into the over-firing nerves in the legs on the muscle end to reduce spasticity in their corresponding muscles by preventing the spasticity signals from reaching the legs; Phenol wears off every six months.

- Orthopedic surgery to release the spastic muscles from their hypertonic state, a usually temporary result because the spasticity source is the nerves, not the muscles; spasticity can fully reassert itself as little as one year post-surgery.

- Selective dorsal rhizotomy, a neurosurgery directly targeting and eliminating ("cutting" or "lesioning") the over-firing nerve rootlets and leaving the properly firing ones intact, thereby permanently eliminating the spasticity but compelling the person to spend months re-strengthening muscles that will have been severely weakened by the loss of the spasticity, due to the fact of those muscles not really having had actual strength to begin with.

Brain MRI shows vermis atrophy or hypoplasic. Cerebral and cerebellar atrophy with white matter changes in some cases.

There is no known cure for cerebral palsy, however there is a large array of treatments proven effective at improving quality of life and relieving some of the symptoms associated with CP, especially SHCP. Some treatments are aimed at improving mobility, strengthening muscle and improving coordination. Although CP is due to permanent damage and is not progressive in nature, without treatment the symptoms can become worse, intensifying in pain and severity, and create complications that were not initially present. Some treatments are preventative measures to help prevent further complications, such as complete paralysis of the arm due to non-use and subsequent worsening hypertonia and joint contracture. Others forms of treatment are corrective in nature. Many treatments target symptoms that are indirectly related to or caused by the SHCP. Many of these treatments are common for other forms of CP as well. Treatment is individualized based on each case and the specific needs of the patient. Treatments are often combined with other forms of treatment and a long term treatment plan is created and continuously evaluated. Treatment can include the following:

- "Physical therapy" – Physical therapy is the most common form of treatment (source needed). It may include sensory stimulation, stretching, strengthening and positioning. Constraint-induced movement therapy is a newer form of physical therapy for SHCP that involves casting or splinting the unaffected arm to promote use of the affected arm (Taub). The theory behind constraint-induced movement therapy is that new neural pathways are created. Alternative forms of physical therapy include yoga and dance. Physical therapy may also include the use of braces while not actively involved with the therapist.

- "Occupational therapy" – Occupational therapy evaluates and treats patients through selected activities in order to enable people to function as effectively and independently as possible in daily life. Occupational therapy is geared toward the individual to achieve optimal results and performance while learning to cope with their disability.

- "Speech therapy" – Due to difficulties in speech, speech therapy is often necessary. Aside from helping with understanding language and increasing communication skills, speech therapists can also assist children that have difficulty eating and drinking.

- "Behavioral therapy" — Psychotherapy and counseling are heavily used in treatment of individuals with SHPD to help them cope emotionally with their needs and frustrations. Counseling through social work can be very beneficial for social issues and adjustments to society. Psychotherapy becomes a more important aspect of therapy when more serious issues such as depression become problematic. Play therapy is a common treatment for all young children with or without disabilities, but can be very useful helping children with SHCP. This therapy again is individualized geared to improve emotional and social development; reduce aggression; improve cooperation with others; assist a child in processing a traumatic event or prepare for an upcoming event such as surgery.

- "Surgery" – Although surgery may become necessary in some cases, physical therapy and the consistent use of braces can help mitigate the need for surgery. Surgical procedures are painful with long and difficult recoveries and do not cure the condition. Most common, is surgery that effectively lengthens the muscle. This type of surgery is usually performed on the legs, but can be performed on the arms as well. Surgeries also may be necessary to realign joints. Other, less popular surgical techniques try to reduce spasticity by severing selected overactive nerves that control muscles. This procedure, known as selective dorsal root rhizotomy, is still somewhat controversial, and is generally used only on the lower extremities of severe cases. Other experimental surgical techniques are also being investigated. The benefits of surgery can also be negated or reversed if the patient does not participate in physical therapy and braces (or casts) are not worn regularly.

- "Medicinal" – Medication targeting symptoms associated with spasticity is also a relatively new treatment that is utilized, but is still in the early stages of development. Drugs such as baclofen, benzodiazepines (e.g., diazepam), tizanidin, and sometimes dantrolene have shown promise in the effort to diminish spasticity. Botulinum toxin ("Botox") type A may reduce spasticity a few months at a time and has frequently been considered a beneficial treatment for children with SHCP and other forms of CP. Botox has been shown to be especially beneficial to reducing spasticity in the gastrocnemius (calf) muscle. This therapy can improve range of motion, reduce deformity, improve response to occupational and physical therapy, and delay the need for surgery. Botox injections have also shown advantages for upper extremities. There is still some doubt for the effectiveness, and some side effects to the relaxed muscles have been a loss of strength for patients with some muscle control. Casting, in conjunction with Botox injections may be an additional option for better results. Research is constantly investing in new improvements and more experimental therapy and treatment.

By most definitions, intellectual disability is more accurately considered a "disability" rather than a "disease". Intellectual disability can be distinguished in many ways from mental illness, such as schizophrenia or depression. Currently, there is no "cure" for an established disability, though with appropriate support and teaching, most individuals can learn to do many things.

There are thousands of agencies around the world that provide assistance for people with developmental disabilities. They include state-run, for-profit, and non-profit, privately run agencies. Within one agency there could be departments that include fully staffed residential homes, day rehabilitation programs that approximate schools, workshops wherein people with disabilities can obtain jobs, programs that assist people with developmental disabilities in obtaining jobs in the community, programs that provide support for people with developmental disabilities who have their own apartments, programs that assist them with raising their children, and many more. There are also many agencies and programs for parents of children with developmental disabilities.

Beyond that, there are specific programs that people with developmental disabilities can take part in wherein they learn basic life skills. These "goals" may take a much longer amount of time for them to accomplish, but the ultimate goal is independence. This may be anything from independence in tooth brushing to an independent residence. People with developmental disabilities learn throughout their lives and can obtain many new skills even late in life with the help of their families, caregivers, clinicians and the people who coordinate the efforts of all of these people.

There are four broad areas of intervention that allow for active participation from caregivers, community members, clinicians, and of course, the individual(s) with an intellectual disability. These include psychosocial treatments, behavioral treatments, cognitive-behavioral treatments, and family-oriented strategies. Psychosocial treatments are intended primarily for children before and during the preschool years as this is the optimum time for intervention. This early intervention should include encouragement of exploration, mentoring in basic skills, celebration of developmental advances, guided rehearsal and extension of newly acquired skills, protection from harmful displays of disapproval, teasing, or punishment, and exposure to a rich and responsive language environment. A great example of a successful intervention is the Carolina Abecedarian Project that was conducted with over 100 children from low SES families beginning in infancy through pre-school years. Results indicated that by age 2, the children provided the intervention had higher test scores than control group children, and they remained approximately 5 points higher 10 years after the end of the program. By young adulthood, children from the intervention group had better educational attainment, employment opportunities, and fewer behavioral problems than their control-group counterparts.

Core components of behavioral treatments include language and social skills acquisition. Typically, one-to-one training is offered in which a therapist uses a shaping procedure in combination with positive reinforcements to help the child pronounce syllables until words are completed. Sometimes involving pictures and visual aids, therapists aim at improving speech capacity so that short sentences about important daily tasks (e.g. bathroom use, eating, etc.) can be effectively communicated by the child. In a similar fashion, older children benefit from this type of training as they learn to sharpen their social skills such as sharing, taking turns, following instruction, and smiling. At the same time, a movement known as social inclusion attempts to increase valuable interactions between children with an intellectual disability and their non-disabled peers. Cognitive-behavioral treatments, a combination of the previous two treatment types, involves a strategical-metastrategical learning technique that teaches children math, language, and other basic skills pertaining to memory and learning. The first goal of the training is to teach the child to be a strategical thinker through making cognitive connections and plans. Then, the therapist teaches the child to be metastrategical by teaching them to discriminate among different tasks and determine which plan or strategy suits each task. Finally, family-oriented strategies delve into empowering the family with the skill set they need to support and encourage their child or children with an intellectual disability. In general, this includes teaching assertiveness skills or behavior management techniques as well as how to ask for help from neighbors, extended family, or day-care staff. As the child ages, parents are then taught how to approach topics such as housing/residential care, employment, and relationships. The ultimate goal for every intervention or technique is to give the child autonomy and a sense of independence using the acquired skills he/she has.

Although there is no specific medication for intellectual disability, many people with developmental disabilities have further medical complications and may be prescribed several medications. For example, autistic children with developmental delay may be prescribed antipsychotics or mood stabilizers to help with their behavior. Use of psychotropic medications such as benzodiazepines in people with intellectual disability requires monitoring and vigilance as side effects occur commonly and are often misdiagnosed as behavioral and psychiatric problems.

Although no specific treatment exists, the disease can be managed with anticonvulsants, physiotherapy, etc.

Treatment of TSP involves corticosteroids to help with inflammation. Though any success with corticosteroids is short-lived, with symptoms worsened as the dosage is reduced. A synthetic derivative, 17-alpha-ethinyltestosterone, can be used to treat Tropical spastic paraparesis, improvement in motor and bladder function was reported but not sustainable.

Mogamulizumab, an anti-CCR4 IgG1 monoclonal antibody, is also being researched as a possible treatment for Tropical spastic paraparesis. The antibody reduces HTLV-1 proviral load and production of proinflammatory cytokines. Valproic acid has also succeeded in reducing the proviral load of HTLV-1 (though clinical benefits were minimal or none). A further combination of valproic acid and zidovudine has demonstrated a decrease in proviral loads (in animals).

Currently, the only effective treatment for encephaloceles is reparative surgery, generally performed during infancy. The extent to which it can be corrected depends on the location and size of the encephaloceles; however, large protrusions can be removed without causing major disability. Surgery repositions the bulging area back into the skull, removes the protrusions, and corrects the deformities, typically relieving pressure that can delay normal brain development. Occasionally, shunts are placed to drain excess cerebrospinal fluid from the brain.

The goals of treatment include:

- closure of open skin defects to prevent infection and desiccation of brain tissue

- removal of nonfunctional extracranial cerebral tissue with water-tight closure of the dura

- total craniofacial reconstruction with particular emphasis on avoiding the long-nose deformity (nasal elongation that results from depression of the cribiform plate and nasal placode). Without proper management, the long-nose deformity can be more obvious after repair.

The outcome of this disease is dependent on the severity of the cardiac defects. Approximately 1 in 3 children with this diagnosis require shunting for the hydrocephaly that is often a consequence. Some children require extra assistance or therapy for delayed psychomotor and speech development, including hypotonia.

Pelizaeus–Merzbacher disease (PMD) is a rare central nervous system disorder in which coordination, motor abilities, and intellectual function are delayed to variable extents.

DOOR (deafness, onychdystrophy, osteodystrophy, and mental retardation) syndrome is a genetic disease which is inherited in an autosomal recessive fashion. DOOR syndrome is characterized by mental retardation, sensorineural deafness, abnormal nails and phalanges of the hands and feet, and variable seizures. A similar deafness-onychodystrophy syndrome is transmitted as an autosomal dominant trait and has no mental retardation. Some authors have proposed that it may be the same as Eronen Syndrome, but since both disorders are extremely rare it is hard to make a determination.

Treatment should be based on assessment by relevant health professionals. For spastic muscles with mild-to-moderate impairment, exercise should be the mainstay of management, and is likely needed to be prescribed by an occupational therapist, physical therapist, accredited exercise physiologist (AEP) or other health professional skilled in neurological rehabilitation.

Muscles with severe spasticity are likely to be more limited in their ability to exercise, and may require help to do this. They may require additional interventions, to manage the greater neurological impairment and also the greater secondary complications. These secondary complications involve the development of contractures, deformity and postural asymmetries. Interventions may include icing, serial casting, sustained stretching, inhibitory pressure and medical interventions. Treatment should be done with firm and constant manual contact positioned over nonspastic areas to avoid stimulating the spastic muscle(s). Alternatively, rehabilitation robotics can be used to provide high volumes of passive or assisted movement, depending on the individual's requirements; this form of therapy can be useful if therapists are at a premium, and has been found effective at reducing spasticity in patients suffering from stroke. For muscles that lack any volitional control, such as after complete spinal cord injury, exercise may be assisted, and may require equipment, such as using a standing frame to sustain a standing position. A general treatment guideline can be followed that involves:

- The initial focus on first activating contraction of antagonist muscles to provide reciprocal inhibition and lengthen spastic muscles

- Reciprocal actions are attempted. Agonist contractions are performed first in small ranges progressing to larger arcs of movement

- Highly stressful activities be minimized early in training

- Functional skills are targeted for training

- Patients and family/caregivers should be educated about the importance of maintaining range of motion and doing daily exercises

Medical interventions may include such medications as baclofen, diazepam, dantrolene, or clonazepam. Phenol injections can be used, or botulinum toxin injections into the muscle belly, to attempt to dampen the signals between nerve and muscle. The effectiveness of medications vary between individuals, and vary based on location of the upper motor neuron lesion (in the brain or the spinal cord). Medications are commonly used for spastic movement disorders, but research has not shown functional benefit for some drugs. Some studies have shown that medications have been effective in decreasing spasticity, but that this has not been accompanied by functional benefits. Surgery could be required for a tendon release in the case of a severe muscle imbalance leading to contracture. In spastic CP, selective dorsal rhizotomy has also been used to decrease muscle overactivity.

Incorporating hydrotherapy in the treatment program may help decrease spasm severity, promote functional independence, improve motor recovery and decrease medication required for spasticity, which may help reduce the side effects that are possible with oral drug treatments. A 2004 study compared the effects of hydrotherapy on spasticity, oral baclofen dosage and Functional Independence Measure (FIM) scores of patients with a spinal cord injury (SCI). It was found that subjects who received hydrotherapy treatment obtained increased FIM scores and a decreased intake of oral baclofen medication. A 2009 study looked at the effect of hydrotherapy to decrease spasticity on post-stroke, hemiparetic patients with limited mobility and concluded that there was a significantly larger increase in FIM scores compared to the control group that did not receive hydrotherapy.

Marinesco–Sjögren syndrome (MSS), sometimes spelled Marinescu–Sjögren syndrome, is a rare autosomal recessive disorder.