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Let us dive into a topic that’s gaining increasing recognition in our field: scuba diving and neurodiversity. As expedition doctors, medics, and nurses, we’re often the first point of contact for adventurous individuals. It’s crucial we have a solid understanding of how conditions like ADHD and Autism Spectrum Disorder (ASD) can intersect with the unique demands of the underwater world.
Imagine this: Sarah, a bright 25-year-old, comes to you brimming with excitement about starting her open water diving course. She mentions, almost as an afterthought, that she has ADHD and is on medication. She’s heard great things about how calming diving can be. So, what’s our immediate thought process? Do we wave her on, or is there more to consider? This article aims to equip you with the knowledge to make informed, safe decisions for individuals like Sarah.
Understanding Neurodiversity in the Diving Context
First off, let’s get our terms straight. Neurodiversity and neurodivergence are umbrella terms that cover a wide range of conditions, often referred to as neurodevelopmental, learning, or developmental disorders. This includes conditions like Attention Deficit and Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder/Condition (ASD/ASC). It’s vital to remember that every individual is unique, and their experience of neurodiversity, and thus their suitability for diving, will vary immensely. There will never be an all-inclusive, blanket recommendation.
The Core Principle: Individual Assessment is King!
This is probably the most important takeaway: every single case must be assessed on its own merits. The degree of disability or impact can be highly variable between individuals. Some neurodivergent individuals might even be more adept than average in certain tasks.
ADHD and the Depths
ADHD is a condition affecting attention, concentration, impulse control, and awareness. It’s one of the most common neurodevelopmental disorders, affecting both children and adults. If not properly managed, these core symptoms can pose risks to scuba diving safety:
- Attention Problems: Individuals with ADHD can be easily distracted by environmental stimuli, making it hard to stay focused on crucial tasks like maintaining buddy contact, monitoring depth, or checking gas supply. While some might experience “hyperfocus” underwater, leading to intense concentration, this can also mean a loss of awareness of the external world, which may be problematic in a diving scenario.
- Impulsiveness and Risky Behaviour: Acting before thinking, making impulsive decisions, or sensation-seeking behaviour (seeking excitement and new stimuli) can lead to poor or risky choices underwater, where risk prevention is paramount.
- Internal Restlessness and Mood Swings: Adults with ADHD often complain of inner turmoil and chaos, and rapid mood changes are also reported. Such internal states could interfere with the calm, controlled mindset needed for diving.
Our advice regarding ADHD symptoms is clear: Diving is not advised if ADHD symptoms are poorly controlled, but, with stable, well controlled symptoms we should do our best to assist inclusivity in scuba.
Medication Matters: A Deep Dive into Psychostimulants
Many individuals with ADHD are on medication, primarily psychostimulants like methylphenidate and dexamphetamine, or non-stimulants like atomoxetine. Here’s what we need to consider:
- Side Effects: Common side effects of stimulants include insomnia, agitation, headache, dry mouth, reduced appetite, and tachycardia. Atomoxetine can cause headache, drowsiness, and increased blood pressure. While generally mild, these side effects could become problematic underwater.
- Rebound Effect: A significant concern is rebound, where ADHD symptoms return and can even be more severe than usual as the medication wears off between doses. Diving is not advised during periods of rebound. This also means we need to consider time zone changes very carefully when travelling prior to diving, as they can disrupt medication schedules and trigger rebound. Evening or night-time diving is generally not recommended as medication may have left the system.
- Single Psychotropic Rule: This is a crucial guideline! Only a single psychotropic medicine (one that affects how the brain works) is allowed. Why? Because more than one psychotropic medicine significantly increases the risk of potentially dangerous side effects while diving, such as increased susceptibility to nitrogen narcosis. The individual must also be compliant with their medication and therapy.
- Cardiovascular Risks: While generally limited in adults, a clinically relevant and continued increase in blood pressure can occur in individual cases. Blood pressure and heart rate checks should be part of routine monitoring for ADHD patients on medication.
- Seizure Risk: This is a serious one. Medications like methylphenidate “should be used with caution in patients with epilepsy” as they may lower the convulsive threshold. Given the potentially fatal outcome of a seizure underwater, and the known increased risk of seizure with elevated oxygen partial pressures, this risk must be thoroughly addressed. Interestingly, there’s an increased risk of epilepsy in children with ADHD, and vice versa. Therefore, diving is not advised in combination with psychostimulants and epilepsy. Dizziness and paraesthesiae as side effects could also mimic Decompression Illness (DCI).
- Hyperbaric Conditions: Frankly, hardly anything is known about how hyperbaric conditions influence ADHD or its treatment. There are indications that psychotropic drugs may increase the risk of nitrogen narcosis and acute oxygen toxicity.
Autism Spectrum Disorder (ASD) and the Aquatic Environment
Similar to ADHD, individuals with ASD who wish to dive require a meticulous, individual assessment. Here are some key considerations:
- Sensory Imbalances: These can cause hyperreactivity to stimuli, which could be aggravated underwater and lead to panic and life-threatening injuries.
- Cognitive Impairment & Decision-Making: Research suggests many people on the autism spectrum have some degree of cognitive impairment, which can affect their ability to make prompt decisions and monitor gauges, depth, air consumption, and buoyancy – all critical skills for a diver.
- Repetitive Behaviour & Coordination: Repetitive behaviours like tics or rocking might make basic underwater skills, such as buoyancy control, challenging and could lead to injury. Some individuals also have challenges with muscle tone and coordination.
- Awareness of Cues: An individual’s awareness of cues and their ability to understand the need to frequently equalize their ears is also vital.
- Co-occurrence: It’s very common for ASD and ADHD to co-occur. Approximately 22% of those with suspected ADHD meet ASD criteria, and 41% of individuals with ASD have suspected ADHD. Co-occurrence of ASD/C and ADHD, other psychiatric problems, or learning disability are likely to be incompatible with independent diving.
- Awareness of the condition, and the specific risks associated with diving, should enable an individual assessment. Once again, the focus must be on safety of all participants, but we should also be mindful of enabling inclusion and equality in participation.
Dyspraxia and Dyslexia: A Nuance in Declaration
Here’s a point where the guidance has a subtle nuance:
- Dyspraxia and dyslexia generally do not need to be declared on the medical screening questionnaire before diving.
- However, dyspraxia can involve delays and impairments in motor co-ordination, movement, balance, learning, organisation, and planning. Such impairments could impact a person’s ability to perform some aspects of scuba diving accurately and timely. Each case should still be assessed on its own merits, especially if the instructor has concerns regarding the degree of disability and its potential impact on diver safety and buddy care.
Screening and the Medical Assessment Process: Our Role
So, how do we guide a patient through this process?
- When to Consult a Dive Doctor:
- Face-to-Face Assessment: For new divers declaring “yes” to any of the above, a face-to-face medical assessment is likely beneficial. This is an ideal opportunity to discuss the safety-critical aspects of diving and potential medication problems.
- Information from Treating Physician: If we have concerns, or if the diver is newly diagnosed or hasn’t developed effective compensatory strategies, we may need more information from their diagnosing doctor. This specialist report should address specific questions like the individual’s capacity to understand and concentrate, follow instructions, cope with stress, manage time, and their capacity to consent.
- Our Role as Medical Referees: We, as medical referees, can certify a diver if there’s no clear contraindication and their medication is stable with no interfering side effects or potential exacerbation by pressure. We might also liaise with specialists or more experienced colleagues if we are unsure. Age is also a consideration; while the general age limit for responsible diving in some guidelines is 14-16 years, for divers with ADHD, an age of 18 years and older is recommended, unless there are strong reasons for us to advise otherwise.
Adjustments and Restrictions: Keeping Divers Safe
If cleared to dive, adjustments or restrictions might be required:
- No “no clear surface” diving.
- No decompression diving.
- Only diving with more than one experienced buddy.
- Depth Limit: A depth limit of 20 metres or 18-20m may be advised depending on the medication taken. This aims to minimise the risk of DCI and the slight theoretical risk that some drugs might increase narcosis.
- Transparency: Divers must make their instructor and buddy aware of their potential disabilities or limitations.
The ‘Blue Mind’ and Positive Aspects of Diving
It’s worth acknowledging the significant benefits many neurodivergent individuals find in diving. As PADI Divemaster Joe Bilbow, who has both autism and ADHD, puts it, scuba diving isn’t just a hobby; it’s a form of therapy, a source of empowerment, and can even be a career.
Many find the underwater environment incredibly calming and relaxing, a stark contrast to the overwhelming distractions of daily life. Scientists call this the “Blue Mind Theory”, where being in or near water induces a meditative state, lowering stress and improving focus. For some, it helps them “switch off” after a dive and provides a release. This sense of calm, control, and confidence can be incredibly beneficial. Joe himself strongly advises consulting a doctor and psychiatrist before starting to dive, especially if on medication, underscoring the importance of our medical assessments.
Conflicts in Guidance?
In reviewing the sources, I found the advice remarkably consistent, often echoing verbatim across different documents, which is great for clarity! The primary “conflicts” are more about nuances or emphasis:
- Dyspraxia Declaration: Sources state it generally doesn’t need to be declared. However, with the caveat that impairments can impact diving and individual assessment is needed, especially if instructors have concerns. This isn’t a conflict, but rather a crucial clarification that “not declared” doesn’t mean “not assessed if concerns arise.”
- Depth Limit: Sources say “A depth limit of 20 metres may be advised,” while another states “Maximum diving depth 18−20 m: a maximum diving depth is advised.” This is a minor difference in wording, from optional advice to a more definitive “advised maximum.” In practice, 20m is a very common recreational limit, and the advice is consistent in recommending a shallower limit.
- Research Evidence Base: Sources explicitly state that there is little research evidence regarding ADHD and diving, and that current guidelines are largely based on “expert opinion.” This isn’t a conflict, but it’s an important piece of information for us to understand the basis of our recommendations. It highlights the need for continued vigilance and caution.
In Conclusion
Our role as medical professionals is to balance the patient’s desire to participate in an activity they find beneficial with the inherent risks of scuba diving, especially for those with neurodevelopmental conditions. A comprehensive, individualised assessment, close liaison with the patient’s treating physicians, and a clear understanding of medication effects and potential underwater challenges are paramount. By doing so, we can ensure that diving remains a safe and enriching experience for all who are safe to participate and do our part to increase inclusion and equality in adventures.
Source Material Used:
• DDRC Healthcare: ADHD & AUTISM
• UKDMC: Attention Deficit and Hyperactivity Disorder (ADHD) and Autistic Spectrum Disorder / Condition (ASD / ASC) – Guidance for Medical Referees
• Divers Alert Network: Autism and Diving
• PMC: Diving and attention deficit hyperactivity disorder
• PADI: PADI Ambassador Joe Bilbow on Diving With Autism and ADHD