How to Tell If Your ADHD Medication Dose Needs Adjusting

Finding the right ADHD medication dose is not a one-appointment process. Titration takes weeks to months, and even once stable, life changes, hormonal shifts, or tolerance can mean a dose that worked well for months stops working as effectively. This guide covers the specific signs that your dose is too low, too high, or that you might be on the wrong medication, and explains how your GP approaches dose adjustment in Australia.

Signs your dose is too low

A dose that is too low means you are tolerating the medication well but not getting adequate symptom relief. This is the most common scenario early in titration, because your GP deliberately starts at the bottom of the dosage range.

Signs to look for:

Core symptoms persist: you still struggle with sustained attention, starting tasks, or following through on plans to a degree that meaningfully affects your day.
The medication wears off too quickly: short-acting dexamphetamine lasts 3 to 4 hours, but if you feel it fading after 2 hours, the dose may be insufficient.
You only notice the medication when it is not there: a subtle improvement that becomes obvious when you miss a dose suggests the medication is working but not at full therapeutic effect.
Procrastination and task-switching remain unchanged: if the patterns that prompted your diagnosis have not shifted at all, a higher dose is worth trialling.
Emotional reactivity stays high: ADHD-related emotional dysregulation often improves with adequate stimulant dosing.

A dose that is too low is safe. It simply means there is room to increase within the therapeutic range. Your GP may raise the dose in small increments at your next review.

Signs your dose is too high

A dose that is too high produces side effects that outweigh the benefits. The line between “effective” and “too much” is individual, but certain patterns are consistent warning signs.

Signs to look for:

Emotional blunting: feeling flat, detached, or like your personality has dulled. Some people describe feeling “robotic” or losing their sense of humour. This is one of the clearest signals that the dose is too high.
Overfocus or hyperfocus on the wrong things: spending three hours organising a spreadsheet nobody asked for, while the task you needed to do remains untouched.
Physical restlessness or jitteriness: an internal buzzing or inability to sit still, distinct from ADHD restlessness. More like too much caffeine.
Anxiety or a sense of unease: new-onset anxiety that was not present before medication or at lower doses. This is dose-dependent and typically resolves when the dose is reduced.
Elevated resting heart rate: a resting pulse consistently above 100 bpm or noticeably higher than your baseline warrants a GP review.
Jaw clenching or teeth grinding: particularly with dexamphetamine and Vyvanse at higher doses.
Significant appetite loss or weight loss: some appetite suppression is expected, but rapid weight loss or inability to eat throughout the day suggests the dose is too high.

Contact your GP to discuss stepping back to the previous dose level.

Signs it might be the wrong medication

Sometimes the issue is not the dose but the medication itself. Amphetamine-based stimulants (Vyvanse, dexamphetamine) and methylphenidate-based stimulants (Ritalin, Concerta) work through different mechanisms. Responding poorly to one class does not predict your response to the other.

Consider whether the medication class might be wrong if:

You have trialled a full dose range without adequate benefit: if you have been titrated to the upper end of the recommended dose range and still see no meaningful symptom improvement, switching class is warranted.
Side effects are persistent across multiple doses: if a particular side effect (e.g., anxiety, insomnia, or nausea) occurs at every dose level, a different stimulant or a non-stimulant medication might suit you better.
The medication works but the rebound is unbearable: severe mood crashes as the medication wears off, despite trying different timing strategies, may indicate the formulation is not right for your metabolism.
You experience intolerable side effects at therapeutic doses: the dose that controls your symptoms also causes side effects you cannot live with. A different medication may give the same benefit without the same profile.

Roughly 70 to 80 percent of adults with ADHD respond well to at least one stimulant. If stimulants as a class do not work, non-stimulant options such as atomoxetine (Strattera) and guanfacine are available in Australia.

How your GP adjusts the dose

Dose adjustment follows a structured process. Your GP increases or decreases the dose based on your reported symptom improvement and side effect profile, not on a fixed schedule. The AADPA clinical guideline recommends monthly follow-ups during titration, with blood pressure, pulse, and weight measured at each visit.

The typical approach:

Start low: begin at the bottom of the dose range.
Increase gradually: raise the dose in small increments at weekly or fortnightly intervals.
Assess at each step: your GP asks about symptom control, side effects, sleep, appetite, and mood.
Find the sweet spot: the target is the lowest dose that gives you good symptom control with tolerable side effects.
Stabilise: once optimised, follow-up appointments shift to every 3 to 6 months or as required for ongoing monitoring.

If you use a Velluto-powered GP, structured follow-up questionnaires are built into the process, making it easier to track changes between appointments and giving you more value from the time you spend with your GP.

TGA-approved dosage ranges for Australian ADHD medications

These are the dosage ranges approved by the Therapeutic Goods Administration (TGA) for adult ADHD in Australia. Your GP prescribes within these ranges based on your individual response.

Vyvanse (lisdexamfetamine): 20 mg to 70 mg daily. Starting dose 20-30 mg, titrated in 10-20 mg increments. Available in 20 mg, 30 mg, 40 mg, 50 mg, 60 mg, and 70 mg capsules. TGA-approved for ages 6 to 55.
Dexamphetamine: 5 mg to 40 mg daily (in divided doses). Starting dose 2.5–5 mg. Maximum 40 mg daily under standard Queensland prescribing authority. Doses above 40 mg require additional approval.
Methylphenidate IR (Ritalin): 10 mg to 60 mg daily (in divided doses, 2–3 times per day). Starting dose 5 mg twice daily.
Methylphenidate ER (Concerta): 18 mg to 72 mg daily. Starting dose 18 mg or 36 mg.
Methylphenidate ER (Ritalin LA): 20 mg to 80 mg daily. Starting dose 20 mg.

Your GP will not jump straight to the maximum dose. The titration process described above ensures you reach an appropriate dose for your body without overshooting.

When to talk to your GP

Book a review with your GP if any of the following apply:

Your medication was working well but has become less effective over weeks or months
Side effects that initially settled have returned or worsened
You have started a new medication (for any condition) that might interact with your stimulant
Your weight has changed significantly (stimulant doses are not weight-based, but body composition changes can affect response)
Hormonal changes (menstrual cycle, pregnancy, perimenopause) are affecting how the medication works
You are experiencing emotional blunting, persistent anxiety, or mood changes
You are considering stopping your medication

Never adjust your dose without consulting your GP. Increasing a stimulant dose without medical guidance increases the risk of side effects and does not guarantee better symptom control. Your GP has the clinical context to make safe adjustments. If you need a starting point for assessment, our ADHD assessment takes under 5 minutes.

Frequently asked questions

How often should my GP review my ADHD medication dose?

During titration (the first 4 to 8 weeks), your GP should review your dose monthly at minimum, with some GPs checking in weekly by phone or telehealth. Once your dose is stable and effective, reviews shift to every 3 to 6 months. The AADPA guideline recommends blood pressure, pulse, and weight checks at each review.

Is it normal for ADHD medication to stop working after a few months?

Perceived reduced effectiveness is common and has several explanations. Tolerance to the initial noticeable effects can develop, though the therapeutic benefit often remains. Changes in sleep, stress, diet, or hormones can all affect how well the medication works. A GP review can determine whether a dose adjustment is needed or whether other factors are at play.

Can I ask my GP to increase my ADHD medication dose?

If your current dose is within the approved range and you feel it is not providing adequate symptom control, discuss this with your GP. Bring specific examples of how symptoms are affecting your daily life. Your GP will weigh the potential benefit of a higher dose against the risk of increased side effects.

What is the difference between the medication wearing off and tolerance?

Wearing off is the normal end of a dose period. Short-acting dexamphetamine lasts 3 to 4 hours, and you will feel it fade each time. Tolerance means the same dose gives less benefit over time at a level beyond normal wearing off. True pharmacological tolerance to stimulants is debated in the research. If you feel your medication is less effective, your GP can help determine whether it is a dosing, timing, or tolerance issue.

Should I take a break from ADHD medication to prevent tolerance?

Medication breaks (sometimes called drug holidays) are sometimes used in children to assess ongoing need, but they are not routinely recommended for adults. Stopping suddenly can cause rebound symptoms. If you are considering a break, discuss the timing and approach with your GP first. Some adults take weekends off short-acting stimulants, but this is an individual decision made with your prescriber.

Dose adjustment is a normal, expected part of ADHD medication management. The right dose is one that improves your focus, reduces impulsivity, and lets you function more effectively without side effects that undermine those gains. Track your response, and communicate clearly with your GP. If you have not yet been assessed, book an ADHD assessment.

General health information

This article is general health information only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always speak with a qualified health professional before making any changes to your medication or treatment plan.

MySpecialistGP is a health information and GP directory service operated by Webbed Feet Pty Ltd. Read our Medical Disclaimer.