ADHD and Memory: Why You Keep Forgetting Things (and What Helps)

Short answer: ADHD can affect memory. Forgetfulness in daily life is one of its recognised symptoms,¹ and ADHD involves difficulties with executive functions, including working memory,² the mental workspace that holds information while you use it. Because ADHD begins in childhood, the forgetfulness it causes is usually long-standing rather than a recent decline.³⁴ If your memory has changed noticeably, or problems are getting in the way of daily life, see your GP.⁵

Does ADHD affect memory?

Forgetfulness is part of how ADHD is defined. The inattention symptoms used to diagnose it include forgetting daily tasks such as chores and errands, and being easily distracted by unrelated things or thoughts.¹ Australia’s healthdirect lists trouble remembering things and losing things among the symptoms of ADHD,³ and being forgetful in daily activities is one example of inattention in adults.⁶

Everyone forgets things sometimes. What matters is how often it happens and how much it gets in the way. With ADHD, forgetfulness might look like:

• losing your keys, wallet or phone several times a week
• forgetting appointments, bills or birthdays unless something reminds you
• walking into a room and having no idea why
• losing your train of thought mid-sentence, especially when you’re interrupted
• forgetting instructions with several steps, or what someone told you a minute ago
• starting a task, getting sidetracked and only remembering it hours later

If forgetfulness and distraction are your main problems, read about inattentive ADHD in adults.

ADHD and working memory, explained simply

Working memory is your brain’s short-term workspace. It holds information in mind while you use it: a phone number while you dial it, the next step in a recipe, or the point you want to make while someone else finishes talking. It’s different from long-term memory, which stores information for later.

The Australian ADHD Guideline lists working memory among the executive functions affected in ADHD, along with planning, sustained attention and inhibitory control (the ability to stop yourself acting on impulse).² When working memory is overloaded, information can slip away before you’ve finished using it. That’s one reason multi-step instructions, mental arithmetic or a busy group conversation can be hard to keep up with. For more on these thinking skills, see executive dysfunction in ADHD.

Why ADHD forgetfulness happens

A few everyday patterns may help explain why things slip through the cracks.

It may never have gone in

If your attention drifts while someone is talking, or while you’re putting your keys down, the information may never be properly taken in. Then there’s nothing to remember later. It can feel like a memory problem when it may have started as an attention problem.

Something else grabs your attention

You might fully intend to send that email, but by the time you’ve opened your inbox, something else has your attention. Remembering to do something at the right time, like returning a call at 3 pm or taking the washing out, also depends on keeping track of time. If that’s hard for you, see ADHD and time blindness. And when something grabs you completely, everything else can drop out of mind — see ADHD hyperfocus.

Planning takes more effort

Planning is one of the executive functions ADHD can affect,² and it’s often planning that sets up the cues that jog your memory, like putting tomorrow’s bag by the door. Without those cues, it’s easy for things to slip.

“ADHD brain fog”: what might be going on?

“Brain fog” isn’t a medical diagnosis. People use it to describe feeling slow, foggy or unable to think clearly. Some of this may be ADHD itself, but several other things can affect memory and thinking, and some of them are common in people with ADHD.

• Poor sleep. Studies report insomnia in 43–80% of adults with ADHD.⁷ Not getting enough sleep can impair memory and attention, and slow how quickly you process information.⁸ See ADHD and sleep.
• Low mood, stress and anxiety. Depression, stress and anxiety can all affect memory,⁵ and many people with ADHD also have anxiety or depression.³ Anxiety can make it hard to concentrate, too.⁹
• Alcohol and medicines. Alcohol and some medicines can also affect memory.⁵ If you think a medicine is affecting your memory, talk to your doctor or pharmacist rather than stopping it yourself.

Because these can overlap, raise brain fog with your GP rather than assuming it’s “just ADHD”.

Is it ADHD or something else, like dementia?

It’s natural to worry about dementia when you keep forgetting things, especially as you get older. A few points can help put this in perspective.

Some memory change is normal. Small changes in memory are part of normal ageing and shouldn’t interfere with everyday life. Forgetting important things more often, or changes that do interfere with daily life, are different: that’s memory loss, and it’s worth getting checked.⁵

ADHD starts early. ADHD is a neurodevelopmental condition that begins in early childhood, and an adult diagnosis needs evidence that symptoms started in childhood.³ If you’ve always been forgetful and distractible, ADHD may be part of the picture. If your memory has got noticeably worse recently, tell your GP, whatever your age.

ADHD can look like mild cognitive impairment. Researchers writing in 2017 noted that ADHD symptoms such as trouble sustaining attention, difficulty organising or multitasking, and forgetfulness can closely resemble mild cognitive impairment (a decline in memory and thinking that can come before dementia), particularly after age 50. The two can also share sleep problems, depression and anxiety.⁴ A key difference is the pattern over time: ADHD reflects long-standing difficulties, whereas mild cognitive impairment usually involves a marked recent worsening. The authors also noted it was unclear whether ADHD is linked to dementia later in life, or is sometimes mistaken for mild cognitive impairment.⁴

For more on how ADHD changes over the years, see does ADHD get worse with age? If you’re a woman in midlife, ADHD and menopause may also be useful.

Practical ways to support your memory

The aim is to take the load off your working memory by keeping information outside your head. These are practical ideas rather than treatments, so try a couple and keep what works for you.

• Capture everything in one place. Write tasks down as soon as they come up, in one notes app or notebook rather than several.
• Use one calendar, with reminders. Put every appointment in a single calendar and set two reminders, such as the day before and an hour before.
• Label your alarms. Name each alarm after the task (“Call the bank”), not just the time.
• Give things a home. Keep your keys, wallet and glasses in the same spot every time, such as a bowl or hook by the door.
• Make it visible. Leave things you need to take with you in front of the door, and put notes where you’ll see them at the right moment.
• Build routines and checklists. Doing things in the same order each morning, or keeping a short “leaving the house” checklist, means less to remember.
• Repeat and confirm. When someone gives you instructions, repeat them back or ask for them in writing.
• Leave yourself a note. Before you stop a task, jot down the next step so you can pick up where you left off.

If you’re diagnosed with ADHD, talk to your doctor about treatment options. The Australian ADHD Guideline recommends offering CBT to adults with ADHD,¹⁰ and CBT can help you develop practical strategies and skills.¹¹

When to see your GP

See your GP if memory problems are affecting your daily life. It’s best to get them checked as soon as you notice a problem, rather than waiting.⁵ It can help to bring:

• a few recent examples of what you’ve forgotten and how it affected you
• when the problems started, and whether they go back to childhood or are new
• notes on your sleep, mood, stress levels and how much alcohol you drink
• a list of all the medicines and supplements you take

Your GP can look at possible causes, including ADHD, and arrange further assessment if it’s needed.

Getting support

If low mood, stress or anxiety are part of the picture, you don’t have to wait for answers to get support. For 24-hour support, call Lifeline on 13 11 14 or Beyond Blue on 1300 22 4636. If you or someone else is in crisis and needs help now, call 000.¹²

Frequently asked questions

Does ADHD affect memory?

Yes. Being forgetful in daily life is a recognised ADHD symptom, and ADHD affects working memory, which you rely on to keep information in mind while you’re using it.

What is working memory in ADHD?

Working memory is the short-term mental workspace that holds information while you use it, like a phone number while you dial. It’s one of the executive functions that can be harder for people with ADHD, so details may slip away before you’ve finished with them.

What causes ADHD brain fog?

“Brain fog” isn’t a medical diagnosis. Feeling foggy or forgetful can come from ADHD itself, but poor sleep, stress, anxiety, depression, alcohol and certain medicines may also play a part, and sleep problems are common in adults with ADHD.

Is it ADHD or dementia?

ADHD symptoms such as forgetfulness can look like mild cognitive impairment, especially after 50. A key difference is that ADHD involves long-standing difficulties dating back to childhood, while mild cognitive impairment usually involves a clear recent decline. Your GP can help work out what’s going on.

Can ADHD cause memory loss?

ADHD-related forgetfulness is usually long-standing rather than a new loss of memory. Forgetting important things more often, or memory changes that affect daily life, should be checked by your GP.

How can I remember things better with ADHD?

Store things outside your head: keep one calendar with reminders, write tasks down straight away, keep your keys in the same spot and build simple routines. Poor sleep affects memory, so look after your sleep too, and CBT can help you develop strategies that suit you.

Next steps

Read effective strategies for managing ADHD in daily life and how to get an ADHD assessment in Australia, or start with the free ADHD self-assessment.

This article is general information only and is not medical advice. Only a qualified health professional can diagnose ADHD. ADHD GP is a private telehealth clinic staffed by AHPRA-registered Australian GPs.

Book your ADHD assessment

References

1. American Psychiatric Association. What is ADHD?. 2025. www.psychiatry.org — ADHD is one of the most common mental disorders affecting children; symptoms must be present before age 12; an estimated 8.4% of children and 2.5% of adults have ADHD; listed symptoms include fidgeting, feeling restless (in adults), talking too much and forgetting daily tasks.
2. Australian ADHD Professionals Association. About ADHD (Australian ADHD Guideline). 2022. adhdguideline.aadpa.com.au — ADHD affects 6–10% of Australian children and 2–6% of adults; heritability 70–80%; symptoms begin before 12 though diagnosis may come later; 60–86% persist into adulthood; inattentive presentation most prevalent; up to 80% of adults have another mental health condition, such as depressive, bipolar, anxiety or substance use disorders, and cluster B and C personality disorders are more common; describes executive-function difficulties (working memory, planning, sustained attention, inhibitory control), brain-maturation and dopamine differences.
3. healthdirect (Australian Government). Attention deficit hyperactivity disorder (ADHD). 2025. www.healthdirect.gov.au — ADHD is a neurodevelopmental condition that begins in early childhood; around 1 in 20 people in Australia has ADHD; it is partly genetic; an adult diagnosis requires evidence that symptoms began in childhood; learning difficulties can occur alongside it.
4. Callahan BL, Bierstone D, Stuss DT, et al. Adult ADHD: Risk Factor for Dementia or Phenotypic Mimic?. Frontiers in Aging Neuroscience. 2017. PubMed PMID 28824421 — Forgetfulness and other ADHD symptoms can resemble mild cognitive impairment after 50; ADHD reflects lifelong difficulties rather than recent decline; whether ADHD raises dementia risk is unclear.
5. healthdirect (Australian Government). Worried about your memory?. 2026. www.healthdirect.gov.au — Depression, stress, anxiety, some medicines, alcohol and sleep problems can affect memory; small changes are part of normal ageing; see your doctor if memory problems affect daily life.
6. Healthy Male (funded by the Australian Government). Adult ADHD diagnosis in Australia: What you need to know. 2026. healthymale.org.au — In adults, impulsivity can look like excessive spending, risk-taking, conflict with others, interrupting and talking excessively; managing finances and meeting work deadlines can be difficult; some adults ‘hyperfocus’ for hours on activities that interest them, and hyperactivity can show as feeling restless and unable to relax.
7. Wynchank D, Bijlenga D, Beekman AT, Kooij JJS, Penninx BW. Adult Attention-Deficit/Hyperactivity Disorder (ADHD) and Insomnia: an Update of the Literature. Current Psychiatry Reports. 2017. PubMed PMID 29086065 — Studies report insomnia in 43–80% of adults with ADHD.
8. Better Health Channel (Victorian Government). Sleep deprivation. 2014. www.betterhealth.vic.gov.au — Insufficient sleep can impair memory, attention, emotional regulation and the speed of processing information; even short-term sleep deprivation can impair these functions.
9. healthdirect (Australian Government). Anxiety. 2024. www.healthdirect.gov.au — Anxiety disorders are the most common mental health conditions in Australia, affecting 1 in 4 at some stage; symptoms include difficulty concentrating; CBT and self-care such as exercise and less caffeine can help.
10. Australian ADHD Professionals Association. Australian ADHD Guideline — summary of recommendations. 2022. adhdguideline.aadpa.com.au — Medication is the most effective treatment for core symptoms, with non-medication treatments adding support (3.1.1); diagnosing clinicians should be registered and trained in ADHD assessment (2.1.1); the diagnosis must be confirmed before starting medication (5.1.2); CBT should be offered to adults (4.2.11); stimulants are first-line for impairing adult ADHD, with heart rate, blood pressure, weight, sleep, mood and anxiety monitored during titration; co-occurring conditions get best-practice treatment.
11. healthdirect (Australian Government). Treatment for ADHD. 2025. www.healthdirect.gov.au — Stimulants are usually the first medicine prescribed; non-stimulant medicines are available for people who experience side effects; CBT can help develop strategies and skills.
12. healthdirect (Australian Government). Mental health helplines. 2025. www.healthdirect.gov.au — Lifeline (13 11 14) offers 24-hour crisis support and Beyond Blue (1300 22 4636) is available 24/7; if someone is in crisis and needs help now, call triple zero (000).

Sources were last checked on 5 October 2026. See all sources used on this site on our Sources page.