The use of stimulants for ADHD has been found to be one of the most effective treatments across all of mental health. This group of medications has successfully treated ADHD for many decades.
There are two main groups of stimulant medications used in New Zealand - methylphenidate and dexamfetamine. Both of these are available as various formulations which mainly differ in the length of time they’re active in the body - ranging from shorter-acting medications (lasting 4-5 hours) to longer-acting ones (up to 12-13 hours).
How stimulants work
Stimulants work on neurotransmitters (chemicals that affect brain signalling), especially dopamine and noradrenaline. They work by helping the functioning of the pre-frontal cortex (the front part of the brain that helps with planning and organising tasks).
The first stimulant medication a person trials will help about 70% of people and 85% of people will respond to one of the two stimulant medication. For more information see:
Pharmacotherapy of Attention-Deficit Hyperactivity Disorder across the Life Cycle - ScienceDirect
These medicines can be especially helpful across the age span with the core features of ADHD. They can help with attention and focus, as well as with features of impulsivity (people describe having more ‘thinking time’). They can also help with regulating emotions.
There is also evidence that if medication is helpful and used consistently, then it can reduce the risk of suicidal behaviours, substance use disorders, accidental injuries, transport accidents and getting in trouble with crime.
The medication is only effective for the length of time that it’s in your system, so only has an effect the day you take it. This relates to both effects that are wanted for treatment, as well as any side effects that may develop.
Side effects
There are potential side effects for all medications, including those for ADHD. These medications are well tolerated by many people across the age spectrum. However, it’s important to be aware of possible side effects that may occur, and to work with your treatment provider if any do develop. Many of these may be short-lived (1-3 days) or mild. Some of these may be manageable by changing the dose of medication or the time that it’s taken, although others may not improve without a change in the type of medication used.
Some side effects from ADHD stimulant medication:
Loss of appetite while the medication is in effect. This can be a problem both in the short-term (leading to irritability and difficulties with sleep) and longer-term (weight loss or, for a child, failure to gain expected weight) which can affect growth or hieght.
Headaches
Irritability when the medication wears off (which may also relate to the lack of appetite as above, or an effect of having to manage high levels of demand at school/work)
Tics can develop, although this relates to a shared factors between ADHD and tics themselves, rather than specifically caused by medication.
Slight increases in blood pressure and pulse, although for the majority these are small and not clinically significant. In about 15% using these medications the increases may be higher and prompt a discussion about other treatment options with the prescriber. Sometimes a lower dose may have less of an effect on this.
Very rarely these medications have been linked to psychiatric problems such as the development of psychosis. However, this is very uncommon with the doses of medications used in clinical practice and is seen more in cases of substance abuse of much larger quantities.
Stimulant use guidelines
There are many different guidelines on the use of stimulants in clinical practice.
Local guidelines have been developed by various New Zealand organisations, including ADHD New Zealand, and published as the:
New Zealand Clinical Principles Framework for Attention Deficit Hyperactivity Disorder | Ministry of Health NZ
The Australian ADHD Professionals Association (AADPA) has also recently updated the:
ADHD Medication Prescribing Regulations & Authorities in Australia & New Zealand
Types of stimulant medications to treat ADHD
Here's a list of the stimulant medication options used to treat ADHD in New Zealand.
Methylphenidate (shorter-acting medications)
Admin Login