Insomnia isn't a diagnostic symptom of ADHD like it can be for depression, anxiety, and bipolar disorder. Some adults with ADHD have problem-free sleep, and might even see sleep as a rare refuge from the waking challenges of the disorder. But there's little doubt that folks with ADHD tend to struggle a bit more with sleep than the average "neurotypical" and in many cases the symptoms can directly interfere with healthy sleep in predictable ways. In this post I'm going to review some of the more common reasons that the ADHD-diagnosed struggle with sleep and hint at a few possible solutions. I'll mostly focus on difficulty falling asleep, which seems to be the issue that is more common and pronounced with this diagnosis.
Direct Effects Of General Hyperactivity
It's not hard to draw a straight line between the symptoms of hyperactivity, whether subjective or behavioral, and being alert, aroused, active, and AWAKE. Sitting still in bed can be just as difficult as sitting still at a desk if intense hyperactivity hits at bedtime or in the middle of the night. Physical and mental restlessness can feel overwhelming when there is nothing external to focus on, and thoughts can come rapidly. If a partner is present, constant fidgeting and adjustment can get you kicked out of bed.
Luckily not everyone who experiences hyperactivity tends to be especially symptomatic at bedtime. Often times the "engine" will run out of fuel by then. Looking at levels of stimulation and physical activity is key in understanding how to control nighttime hyperactivity but it's easy to overgeneralize. For some people what is important is to get as much total mental and physical stimulation over the course of the day to get tired out. For others, excessive stimuli can get them "wound up" and it is important to find strategies for calming or limiting stimulation starting in the late afternoon or evening. In general limiting certain types of intense stimuli (especially electronics) just before bedtime is important, although that's true of almost everyone. The effects of evening exercise are unpredictable: it can be a positive tool for some, while for others it can stoke hyperactivity like nothing else.
When simple hyperactivity is causing sleep problems, that is the one situation where bedtime stimulant medication might be considered. Always consult with your psychiatrist before trying an unconventional dosing strategy. But people who are strongly hyperactive, especially those who have a predominantly hyperactive-type diagnosis, sometimes become calmer or even drowsy with the right dose of medication. Early in my career I worked at a foster facility for severely emotionally disturbed teenagers. In general I felt that many of them were severely overmedicated, but one big exception was the residents with ADHD who took a bedtime stimulant dose. It would calm them without knocking them out or making them groggy in the morning. On occasion residents would run out of meds, refuse their meds, or "cheek" them to trade with other residents. This would generally result in a very hyper, and very unrestful, night for them.
Circadian Shift And "Eveningness"
This issue might be a little more controversial, but just a little. Nearly every Psychiatrist I have spoken with acknowledges that adults with ADHD tend overall to have patterns of activation that tend to peak later than average. In common parlance this is called being a Night Owl, but it's also something that many of us experience as teenagers or young adults then grow out of, starting to experience more morning preference and desire for earlier bedtimes with age. Much of this is based on social conditioning and work-life demands, but not all of it. Some people's bodies send signals that make it easier to stay up late, harder to get to sleep early, and much more difficult to awaken and become active in the morning. People with ADHD are much more likely to fall into that category. And I want to emphasize: this isn't just true for people with hyperactive symptoms. It's true of predominantly inattentives too.
There's three silver linings here. The first is that there's not necessarily anything wrong with being a Night Owl. Arguably, being able to stay up late makes you inherently cool. If you can adapt your lifestyle to suit a late bedtime and wakeup, this really isn't an issue. The problem is that oftentimes life (bosses, partners, children, dogs, cats) want us to live in the harsh light of morning. The second silver lining is that generally the same approaches that help non-ADHD Night Owls work for their diagnosed brethren. These include morning lightbox therapy, increasing sun exposure during the day, vitamin D, melatonin, and limiting light exposure (especially blue lights) towards bedtime. The third silver lining is that working on circadian issue might help your ADHD symptoms, but no promises there.
If sleep problems predictably get worse during a certain time of year, be it summer or winter, that can be a pretty good sign that there's a circadian component. Unlike with depression where (if there's a seasonal pattern at all) winter tends to be worse, this type of sleep issue could be exaggerated in either season depending on your unique configuration.
Hyperfocus And Poor Routine
There are elements in this section that I think most ADHD sufferers will relate to. Ask any sleep expert about effective treatments for insomnia and I doubt any of them will make it three sentences without using the word "routine", often paired with "bedtime". People with ADHD have wildly varying opinions on routine. Many feel that the monotony and sameness produced by routine is the perpetual enemy, the cause of all boredom, the killer of motivation, the wellspring of all brain fog. Others swear that routine has saved their life, it is the only way to make their unpredictable mind conform to the demands of this world, and calm and prosperity follow in it's wake. But one thing that most people with ADHD can agree upon is that maintaining routine is a challenge. The symptoms of the disorder act in ways that undermine routine.
Distractability is a huge enemy of routine. A cartoonish but incredibly common example: it's easy to get distracted and forget to go to bed! But even more banal distractions can stretch out nighttime activities of all kinds in ways that push back bedtime. Impulsivity is also a big factor. Night can feel like a relatively consequence-free time to chase whims, and you can always make up sleep tomorrow night. Or the next night. Etcetera. Arousal levels in ADHD tend to be very tightly correlated with interest levels. And often obligatory daytime activities are inherently uninteresting almost by definition. So the day is spent in a sheepish, sluggish, muddled haze. Then night comes and the freedom exists to do something ACTUALLY INTERESTING. The mind awakens. Mood improves. And it's time to shut the lights out? I'm sure you see the problem.
Not everybody with ADHD even can hyperfocus if they try much less do it unintentionally, but this tendency can make everything far worse at bedtime. Say a hypothetical guy with a tendency to hyperfocus (John Foci) fights distractions and temptations to finish his chores and dinner and get ready for bed at a reasonable time. He's in bed but his mind is still a little spun from the day so John decides to give in to his urges just a little and check out some scores or watch a video on his phone. Everybody knows playing with the phone just before bed isn't the best thing for sleep but for many people, even many with ADHD, it's also no big deal. Not so for John. Sometime around 3 AM John becomes suddenly aware of his surroundings, staring at one of the strangest websites he has ever seen. "How did I even get here?" John thinks. A search of his browser history reveals a classic 'Wikipedia rabbithole' that somehow burrowed through topics as diverse as the topography of Guyana, Detroit proto-punk, Catholic Biblical Apologetics, and an overview of non-reproductive sexual practices in the family Mustelidae. John is screwed at work tomorrow.
This is a big topic, too big to do justice in this overview. My point is really that ADHD symptoms can cause problems for sleep functioning in fairly similar ways that they can impair functioning in other domains of everyday life. Sleep takes up time and it involves tasks. If it isn't prioritized, that has consequences. Rather than financial or social consequences, consistently failing to sleep enough will usually have symptomatic consequences. Poor sleep means poor focus, and poor focus can lead to bad sleep. As life responsibilities and demands on time and attention escalate, this snake can slowly eat it's own tail, as symptoms become less and less manageable. This is often part of the fulcrum that brings people in to treatment. And often times it is the more global skills of time-management, task-management, impulse control, routine, and organization that "fix" sleep over time in the same way that they can fix problems at work or in relationships. It's a slog. I know, sounds boring to me too. You want a silver lining? Sometimes the crash of coming off medications can make you really sleepy if you time it right.
Various Substances
First off, ADHD medications can absolutely cause insomnia in some people. If you think that might be you, absolutely involve your psychiatrist or PCP in the conversation, and don't do anything without their approval. The easiest fix is to dose earlier, especially with any kind of extended relief preparation. Some people even set an extra alarm, take their meds, and snooze for awhile before wakeup. A change in medication could definitely be worth a try, but a dosage reduction could also definitely be in order. If you are in the habit of taking "holidays" from medication this could be contributing to the insomnia because it is decreasing tolerance. Whatever the fix, in the long term tolerating insomnia to get the effects of a high dose of medication is not worth it. Your health is too important to burn the candle at both ends that way.
People with ADHD are more likely to use, and use higher amounts of, basically any drug. There are lots of reasons for that and I won't go into it here but just trust me, it's true. Unlike stimulant medications which can affect sleep in a variety of ways, caffeine and nicotine tend to be bad for sleep when taken late. Even in these cases there's some outliers, but treating medication crashes with night coffee is a very suspect practice. Alcohol, marijuana, and other recreational drugs often seem like they help with sleep but usually they are degrading it substantially, especially when it comes to the high-quality REM sleep that is most regenerative. But this is true for everyone.
I'm going to engage in a bit of speculation in this last section about a possible issue for people with ADHD using depressants. It's based on clinical experience but I haven't found research or other corroboration to back it up. Here's what we do know:
(1) The treatment of ADHD with stimulants, and in fact the overall understanding of the disorder, has historically been based on something called the "paradoxical reaction" to stimulants. Stimulants should be expected to increase activity level but it was found that for many children who were already very hyperactive, stimulants decreased their activity level and seemed to calm and slow them. Probably a bit too much was made of this paradoxical reaction, Psychiatry is famously prone to overreach and overgeneralization. In fact many children who are not hyperactive still become more sedate when given a dopaminergic stimulant, and many of the benefits that an average ADHD suffer gets from medication are the same benefits that a person with normal attention would get if given the same medication. Still, there is definitely a tendency for those with ADHD to be less stimulated by stimulants, and in some cases to experience aspects of sedation from stimulants.
(2) It's also fairly common for people to experience a "paradoxical reaction" to depressants. Many people will take a downer and become excited, boisterous, and rowdy. Arguably most people have at least some paradoxical effects from a low enough dose of alcohol. Generally this is seen as being mostly due to impulse inhibition and mood lift, and it makes a bit of sense given alcohol's complex pharmacology. But there are also much weirder and rarer cases of people becoming very restless and agitated on high doses of sedatives like Ativan, even leading to angry outbursts and aggression. Marijuana can be a very unreliable sedative, often leading to anxiety, racing thoughts, and increased heartrate, although much of this depends on dose and strain. The same is true for opiates, which some people find quite invigorating despite their usual reputation as quite soporific.
So here's the more speculative bit: I think people with ADHD are more likely to experience a paradoxical reaction to sedatives as well, especially less reliably sedating sedatives like alcohol, marijuana, and opiates. Drugs can alleviate boredom. This is cited again and again by users but especially users with ADHD, who are often more drawn to depressants because they associate stimulants with a treatment effect rather than a recreational effect. Like I mentioned above, levels of overall arousal and activation for those with ADHD can be really tightly tied to levels of interest or perceptual stimuli. In those with ADHD the boost in arousal associated with relief of boredom could more often be powerful enough to overcome the more inherently sedating effects of these drugs. I've definitely seen anecdotal evidence of this in clients and acquaintances with the diagnosis. If it's true that there is an association there, it should give extra pause to people with ADHD about using recreational sedatives near bedtime. I'd be very interested in paradoxical reactions to sedatives that you have experienced in the past if you have an ADHD diagnosis.
Can you tell I'm rabbitholing?