Overview of Common Headache Types & Symptoms
Generally headaches can be separated into two main categories. There are primary headaches, where the headache is the condition itself and secondary headaches, which are caused by an underlying condition or some other factor.
Most people have probably experienced a temporary cold or flu at some point in their life, thus have probably experienced a cold-associated headache. This type of headache would be a secondary type of headache.
The most common type of headache is tension-type headache. Statistically, the vast majority of the population has experienced a tension-type headache at some point. Tension-type headaches are the type of headaches that feel like a band of pressure around your head or a kind of tightening or squeezing feeling.
The pain is usually located on both sides of the head at once. The quality of the pain is usually a sort of a dull, aching type feeling and is usually fairly constant.. In terms of intensity, we generally call these headaches mild to moderate, however some people can experience severe tension-type headaches.
Tension-type headaches typically last for a few hours. Unfortunately for some people, they can last all day or even for multiple days in a row. Often tension-type headaches are associated with tension or tightness in the muscles and neck, which is where they originally got their name.
The next most common type of headache is migraine. Migraine is different to tension-type headaches in that they usually affect only one side of the head, although migraines can switch from side to side between attacks or even during the same attack . The pain quality is quite different to a tension-type headache as well. Instead of being that sort of dull, constant ache, it’s usually a throbbing type pain.
The pain intensity of migraine is generally higher than for a tension-type headache. The pain intensity of migraine is typically described as moderate to severe. For most people the duration of migraine attacks are a little bit shorter than tension-type headaches, however untreated migraine attacks can last anywhere from four hours to three days and beyond.
Migraine attacks are associated with several other symptoms as well as head pain. For example, nausea and vomiting is very common. People can also experience extreme sensitivity to things like light, sound and even smell can trigger more pain or discomfort.
Some people with migraine also experience an aura. Auras are a neurological phenomenon that occur just before the migraine starts, before the pain kicks in. Any of our five senses can be affected. The easiest to recognize are visual changes. People may see flashing lights or perhaps halos around lights, or may experience temporary blind spots. Auras may also cause temporary changes in sensations; people can experience numbness, pins and needles, vertigo or dizziness. The aura phase in a migraine attack can be quite varied, and usually wears off as the headache pain starts to develop.
The other changed that occurs with migraine is that the gastrointestinal system slows down. This can be a problem if you are trying to take medications to treat the headache because it takes longer for those medications to be absorbed and start working. It is for this reason that it is suggested to take migraine medications early on in the attack, before the gut starts to slow down.
Cluster headache is not very common, but it is an important headache type to recognize. Cluster headache pain is easy to pinpoint. Many people with cluster can identify the exact location of the pain which is usually behind one of the eyes.
The pain is severe. Cluster headache is known as the ‘suicide headache’ due to the severity of pain. The type of pain is also different to other primary headache types. In migraine, people tend to want to lie down and rest in a dark and quiet space. With cluster headache, people become physically agitated and may be restless, or unable to sit or lie still due to the intense pain.
While the pain severity is severe, fortunately the duration is short. Cluster headaches are named this way because the short headaches come in rounds. Patients will experience a cluster of these very severe headaches which will often then subside prior to another cluster attack, with people often experiencing a group of clusters over a few weeks at particular times of the year.
Other symptoms or characteristics of cluster headache include a running eye, constricted pupil, droopy eyelid and runny nose on the same side of the face as the headache pain.
How many Australians have headache
Around 12 million Australians that suffer from migraine and/or tension-type headaches combined.
In Australia, sufferers generally tend to be pretty self-reliant. Most people will elect to self-manage their own headache. Nine out of 10 people say that they will self-manage, rather than going to see a doctor for their headache, even if that headache is severe.
About 1% to 2% of the Australian population are thought to suffer from a condition called medication overuse headache . Medication overuse headache has a controversial name. The name may imply blame on the person who has the headache condition, which is completely unfair. Medication overuse headache is associated with frequent use of medications, analgesic medications and migraine specific medications that are used to manage those acute attacks. We will discuss this type of headache further shortly.
Common over-the-counter treatments
There are lots of options available over the counter for managing headaches. Paracetamol and ibuprofen (i.e. Panadol® and Nurofen®) are two medicines commonly used for headache. As absorption of medicines slows down during migraines, sometimes using a soluble formulation can make all the difference. If you have tried regular paracetamol and it hasn’t worked, it might be that actually it’s just not being absorbed well enough, and switching over to a soluble product might help.
The same applies for aspirin. There is good quality evidence showing that aspirin is quite effective in migraine, and there are soluble formulations available for aspirin as well.
There are also a whole range of other anti-inflammatory medicines aside from just aspirin and ibuprofen. These include diclofenac (Voltaren®), naproxen (Naprosyn®) and several others which are available over the counter.
The good news is that even if your migraine does not respond to one type of anti-inflammatory medicine, it may respond to another type of anti-inflammatory medicine. It can be a process of discussing with your doctor or pharmacist and working through the options one by one to see which one works best for you.
If an anti-inflammatory medicine is not sufficient, there are products now that combine paracetamol and ibuprofen in a single tablet. Studies have shown that using those two products together can deliver a greater benefit than using either one alone, and they are safe to use in combination. Panadeine Forte® is a widely used prescription pain medicine. Panadeine Forte is often thought of as a high strength treatment option for patients – because it’s only available with a prescription many people believe it must be strong. However, we now know that the combination of paracetamol and ibuprofen is more likely to be effective than the combination of codeine and paracetamol, which is in Panadeine Forte®.
Other options for migraine management are the anti-nausea medications that are available over the counter. Nausea is a common symptom of migraine. Studies have also shown that anti-nausea medications, particularly one called metoclopramide, in addition to helping with the nausea, actually improve the way other pain medicines work as well. Anti nausea medications are can help with the absorption of pain treatments. In migraine, when the gut slows down, those nausea medicines help to keep the gut moving and to increase the absorption of other pain medicines so that they work more effectively.
There are also pain medicines available over the counter which are combination products. These products contain paracetamol and something else to help modify the way that paracetamol works for pain. One example is a combination of paracetamol and caffeine. In Australia this combination is available in Panadeine Extra®. There is also another product that’s relatively new to the market that contains paracetamol and a sedating antihistamine. And the point of that sedating antihistamine is = to help you get to sleep if you’re suffering a migraine, because we know that sleep itself is actually very helpful at terminating a migraine attack.
Medication Overuse Headache
Unfortunately, some medicines that we use specifically to relieve headache pain can worsen the headaches over time. This tends to predominately occur in patients who have a pre-existing headache disorder (like migraines or tension-type headache) and thus it is not a side effect of the medication, instead it’s an interaction between the headache condition and the effects of the medicine.
The chart above shows someone with a pre-existing headache condition such as regular tension-type headache or regular migraine attack. In the first graph section, the spikes indicate migraine attacks that have been treated. This individual is taking analgesic medications frequently for their headache because they have frequent attacks. Over time it is common for this type of treatment pattern to result in an increase in headache frequency (as shown in the chart). Interestingly, if you have someone with another pain condition, arthritis, for example, and they don’t have a headache condition, but they take the exact same general pain medicines in the exact same doses for the same period of time, they don’t develop frequent headaches.
If you have tension-type headache and you start taking lots of pain medicines you can might experience an increase in the frequency and the duration of those tension-type headaches. Frequent use of pain medicines by people who suffer from migraines can result in more frequent migraine attacks. In addition, it can also create an underlying tension-type headache pain in-between migraine attacks.
So if you suffer from migraines and you start to notice dull, more mild headaches in-between the migraine attacks, it might be useful to reflect on pain medicines that you’re using, and how often you’re using those medicines. It would be worth discussing with your doctor as a migraine preventative medicine might be helpful.
Medication overuse headache can be difficult to treat and it can become a long and slow process of trying other things to manage the underlying headache and while slowly cutting back on the amount of those acute pain relieving medicines that the person is using.
It is very important if you are self-managing your headache that you speak with someone about the medicines you are taking as not all treatments are suitable for everyone, even if they’re available over the counter. There are certain medications and medical conditions that can interact with other medicines, so it’s important to speak to your pharmacist or doctor to discuss treatments.
In addition to medications, there are many lifestyle changes and other non-drug strategies that you can try to help with headaches.
Often an ice pack at the base of the skull for migraine or a hot pack across the shoulders for a tension headache can be helpful. In terms of lifestyle, sleeping with a regular pattern, eating on a regular basis to keep your blood sugar levels consistent, exercising, and drinking enough water, can be beneficial for some people to minimize the impact of headaches. Although these changes may not be sufficient to eliminate all your attacks they can make a significant difference.
If over the counter options and lifestyle changes are not sufficient then there are many prescription options available from your doctor.
The class of medicines called ‘triptans’, currently available only on prescription, can be very useful for migraine. These do not have some of the side effects of other prescription pain medicines and tend to work quite quickly. Unfortunately this class of treatment does not work for tension-type headaches.
Triptan medicines that are injections or nasal sprays can be beneficial for people that have problems with nausea and keeping tablets down during the migraine phase. The other thing with these triptan medicines is that if you don’t respond to the first one you try, you might still respond to the next one or the one after that. There are currently five different triptan medications available in Australia.
If you find that you are using acute treatments to help manage your headache on a regular basis it would be worth talking to your doctor about preventative medications.
Most of the medicines used to reduce the frequency of headaches were actually first used for other conditions. For example medications for migraine prevention have been taken from medications that were developed originally for seizures, managing blood pressure or depression. There are several options which come from a range of different drug classes and the choice can be tailored based on the health profile of the individual and the medicines potential side effects.
Chronic migraine is diagnosed when someone experiences 15 days of headache patient each month and many of these headaches have migraine features. For people which chronic migraine, a specific chronic migraine treatment like Botox® could be an option.
Care should be taken regarding the use of codeine in the setting of chronic migraine. We conducted a pre-clinical study at the University of Adelaide a number of years ago which found that giving repeated doses of codeine over time actually increased sensitivity to pain. Medications such as codeine and Endone® may be useful for some headache sufferers however they have lots of side effects and other options should be considered first. These medications should only be used to manage headaches under specialist advice. Often these medications are sedating and can assist in promoting sleep, and the sleep helps to terminate the attack, rather than the drug itself.
Natural Alternatives & Complementary Medicines
Complementary medicines is a term that is frequently used in a variety of contexts in Australia, capturing a large range of different alternative therapies from herbal medicines, traditional Chinese medicines, homeopathy and aromatherapy and also encompasses vitamin and mineral supplements.
Natural Doesn’t Always Mean Safe
There can be a perception that because a treatment is available from a health food shop or the supermarket that the risks of using these treatments must be low. Unfortunately that is not always the case. It is important to remember that even natural alternatives are ‘medicines’ – anything that affects biological processes in the body can be considered a medicine. They all have risks and benefits, and health professional guidance is always recommended to help in weighing up the pros and cons of each option.
Regulation of Natural Alternatives
Like prescription medicines and over the counter medicines, many natural medicines and supplements are regulated in Australia by the Therapeutic Goods Administration (TGA).
There are two main categories for medicines that are available over the counter. They can be either categorised as a listed medicine or as a registered medicine. Any prescription medicine will be registered (as shown in the right-hand column in the image above). Most natural medicines will be listed medicines and considered to be lower risk in general or used to manage lower risk conditions.
All listed medicines are assessed for safety and quality, however unlike registered medicines, listed medicines are not assessed for effectiveness. Listed medications can claim to be effective based on their ‘traditional uses’ and are not required to show any evidence from clinical trials or other research to prove that the medication will do what it says on the label.
Registered medicines are required to provide evidence to the TGA so an evaluation of the evidence and the medicine’s claims can be assessed.
These three products are examples of products that contain fish oil. The first one on the left is an AUST R product so it’s registered. It’s actually a prescription only version of fish oil that’s used for a particular type of high cholesterol. As shown in the little green box, there’s the code that says AUST R and then there’s a number.
The product in the middle is a Blackmores Fish Oil® (this example was randomly selected, the author has no affiliation with Blackmores®). As you can see the Blackmores product has AUST L on the label which confirms that this product is a listed version of fish oil.
The prescription product has been assessed for quality and safety and efficacy to make sure that actually delivers what is promised. The Blackmores® product has also been assessed for safety and quality, but there is no formal process for assessing whether or not it’s effective for the conditions it has indicated on its packaging.
On the right side, the third product, is an unscheduled medicine. This is not something that you would usually buy in a pharmacy. It might be something you could see in a health food store, or maybe purchase online. It hasn’t gone through the medicinal regulatory process in Australia. If you have a look on the label, there is no AUST code, which means that it hasn’t been assessed by the TGA for safety or for quality.
Be Careful Buying Online
Always exercise caution when purchasing medicines, even natural medicines online. Unfortunately not all websites are credible and can deceive shoppers.
We would suggest having a conversation with your pharmacist or health care professional to ensure that the natural medicine is not going to interact with anything else you are taking and is safe and appropriate for the condition you are treating.
Homeopathy is a based on a number of different principles. The first principle is that like treats like. For example, caffeine may be used to treat insomnia in a really low dose, with the believe that a really low dose will stimulate your own natural response to overcome that caffeine and that will help you get to sleep.
The dilution process is also another big part of homeopathy. This is where the ingredient that’s going to be used as the ‘cure’ is used to create a mother tincture. That ingredient is mixed in with either alcohol or distilled water to make a solution. Then that solution is diluted again and again and again and again and again to get a really, really low concentration product.
The concentration is so low it is difficult to describe. For example, there are some products will describe their concentration as ‘30C’. The ‘30’ here does not refer to the number times the tincture has been diluted. 30C refers to dilution by a factor of 1060 – to explain that in a more meaningful way that is roughly the equivalent of putting one molecule of the original ‘cure’ in the entire Atlantic Ocean. It’s an incredibly dilute solution. In reality this means when you buy the product off the shelve the chances of it containing a single molecule from the original mother tincture is very, very low.
There is no evidence to support homeopathy in the management of headache or migraine. That aside, If you are seeing a homeopath and you have a good relationship with them, then this can be valuable, the therapeutic relationship might be more valuable than the medication or product given itself.
Commonly Used Natural Remedies For Headache
Listed below are some of the more commonly used natural medicines for headache:
- Fish oil
- Peppermint oil
- Willow bark
- Yerba mate
Most of the natural products available for migraine and tension-type headache are used as preventatives. There are not many natural instant analgesics. Peppermint oil might have some role in acute treatment, but most of herbal products are used to reduce headache frequency rather than treating an acute attack.
Of those listed, Willow bark and Yerba mate have weaker evidence and are less commonly used for headache.
Feverfew is one of the key herbal products that is used for migraine as a complimentary option. It’s used primarily for migraine prevention rather than acute treatment.
Feverfew potentially reduces the severity of pain associated with migraines, as well as reducing other migraine symptoms such as nausea, vomiting and sensitivity to light and sound.
The evidence for feverfew is mixed depending on what study you read. This is thought to be due to the variability in the feverfew products that were used in the research. With herbal products, it is not as simple as just weighing an equivalent amount of dry product and using that amount across different studies. It is much more complicated because the actual active component within those herbs can be dependent on the way the plant was raised. It might be that herbs grown in different places contain different amounts of the active constituents of the herb, even though the same plant might be used in two different preparations. It is difficult to get a standardized approach when doing clinical trials for herbal products, which is why you often see differences in the results.
For feverfew there is some evidence to show that it effective as a migraine preventative medicine. It is well tolerated. When taking feverfew, the risk of side effects is low, and it has been compared with other prescription medicines for treating headache.
There is one potential concern with feverfew with reports of a syndrome called post-feverfew syndrome. This can occur after taking feverfew for a long time and then stopping. The symptoms can include anxiety, insomnia, and aching muscles and joints, but these are temporary.
Riboflavin is one of the natural products that is recommended in the Australian Therapeutic Guidelines as an option for migraine prevention.
Riboflavin is the name that we give to vitamin B2, which is one of the water-soluble vitamins that we should be getting in our diet to some degree. In high doses it is used for migraine prevention. This dose is much higher than what you would normally get from food.
The clinical research for riboflavin is promising. We do see that that efficacy or the effect of it tends to decrease with lower doses; higher doses appear more beneficial. Being a water-soluble vitamin, our kidneys are really good at clearing riboflavin out of our system if we have too much, resulting in less side effects because your body simply excretes what you don’t need.
The most common side effects is excessive urination and the colour of the urine might change, although this is nothing to be concerned about. Riboflavin may also be associated with diarrhoea as well.
Caution should be taken if you have a pre-existing kidney disorder that means you are unable to clear the vitamin as easily.
We know that people who have migraine are statistically more likely to be magnesium deficient than the general population. Common symptoms of low magnesium include cramping, muscle twitches, fatigue and muscle weakness. Supplementing magnesium can have quite a profound effect in reducing migraine attacks.
Magnesium may be used in hospital to help treat an intractable migraine attacks and is usually well tolerated. If you are considering magnesium it is worth speaking to your doctor about testing your magnesium level or with a pharmacist about any medicines you take to see whether or not they might be related to magnesium depletion.
Peppermint Oil has been studied in tension-type headache as opposed to migraine. There is some evidence to support its use in topical application to the skin on the forehead and around the temples. Usually, products are presented as a little roll-on device. These are used to help relieve pain during the headache.
Oils can vary in purity and can be diluted or contain contaminants. It is important to purchase ‘therapeutic oils’ from a reputable source.
If you have purchased an undiluted oil it may irritate the skin when applied. In some cases fumes from concentrated oils can cause lung spasms. If you have asthma, you may be at a higher risk of this complication.
Capsicum or Capsaicin
Capsaicin is essentially the hot part extracted from chilies and can be useful for cluster headaches. It has been incorporated into creams that you buy over the counter and brought into western medicine because it is known to be quite effective for some other types of nerve pain.
In cluster headache there are nasal spray products with capsaicin that are used for treatment. If you’ve ever had chili on your hands and touched your nose then you know that feeling of capsaicin on your skin and you can probably imagine how intense it would be if that was sprayed up your nose. It is thought to work by desensitising the tissue in that area.
Regular use over a week has been shown to reduce the frequency of cluster headaches the next week. In addition to reducing the number of cluster headaches it may also reduce the severity of the headache as well. Not surprisingly, it can burn, particularly those membranes inside the nose but also your skin as well. Sneezing is a common side effect. Most of the studies that have investigated these products actually use an anesthetic beforehand as well to try and alleviate some of that burning, while still retaining the benefit of using the product.
Fish oil has been included in this list as it has been proposed to assist in migraine and is readily available. However there is no evidence to show that using fish oil prevents migraines specifically.
If you’re taking fish oil for another condition, it might be that you do see an improvement in your migraine condition, however we do not currently have enough data to support recommending it for migraine management.
Butterbur is a herbal product derived from the leaves of the plant. It has been shown to reduce the frequency, intensity and duration of the migraine.
One study found a substantial reduction in migraine frequency of nearly 50%. This result is in line with the prescription medicines that we use to reduce headache frequency. Doses in the higher range are needed to see that effect. Butterbur is something that has been tested in children with migraine as well.
Importantly, there is a compound in these herbal extracts that can be dangerous for the liver. If buying this product, it’s important that you do have a look on the label and make sure you buy one that is certified PA free which means it does not contain the component associated with potential liver issues. Other possible side effects include upset stomach, diarrhoea and allergic responses.
Coenzyme Q10 (CoQ10) is an enzyme naturally found in our bodies. In high doses, it may be used to help prevent and reduce duration of migraine as well as the severity.
CoQ10 is also listed in the Australian Therapeutic Guidelines as a natural option for migraine prevention.
Evidence from studies to date show around a 30% reduction in migraine frequency. There was one review that investigated the effect on frequency over five different studies. This review found that although the actual number of attacks didn’t decrease, the number of total days that people spent with migraine did decrease. Participants in the study had the same number of attacks, but each attack was shorter. The actual burden in terms of quality of life was reduced with the CoQ10.
CoQ10 is generally well tolerated however may cause some mild gastrointestinal symptoms.
The hurdle with this medicine is that you have to take it for quite a while before you know if it works. For many prescription medicines, you often need a six to eight week trial to know whether or not that’s the right preventive medication for you. For CoQ10, it might take up to three months before you start to see an improvement.
In terms of natural medicine, there is strong evidence to show that caffeine provides a benefit in enhancing pain relief and can have some mild analgesic properties on its own.
Most evidence shows caffeine is able to increase the effect of other analgesic medicines. The combination with paracetamol is a good example of this. Caffeine can be used to boost the effect of the paracetamol particularly in both tension-type headache and in migraine.
More generally, caffeine intake itself may help or hinder depending on the individual. For some people, they find that caffeine actually can trigger headaches, and for other people, if they don’t have the caffeine, they experience a withdrawal headache. Some people find they need to keep a consistent level intake of caffeine to minimise their headaches.
It is important to remember to keep track of the caffeine from the different sources that you’re consuming. If you get caffeine from coffee and then you start taking your herbal products that also contain some natural caffeine it can add up. This also applies if buying over the counter medicines that contain paracetamol and caffeine.
Side effects associated with caffeine can include irritability, nervousness, heart issues, stomach ulcers and being unable to sleep.
Common Sources Of Caffeine
Above are some examples of naturally occurring caffeine sources. Not listed above are all the beverages that we know of such as Coke®, Pepsi® etc.
For reputable information the NPS Medicine Wise website is a resource worth considering. NPS a not-for-profit organization that aims to provide information for not only health professionals but also consumers. Information on herbs, supplements and more can be found by searching their website.
Placebo responses to medications
The ‘placebo response’ tends to a negative reputation. It is often used to say something is not an active medicine, “it’s just a placebo”. The truth is every treatment contains some component of the placebo effect. Even with registered prescription medicines, they’ll have some biological effect and a non-specific or ‘placebo’ effect. This biologically active molecule will have an impact on your physiology which causes the specific effect of that treatment. Associated with the treatment are a whole range of contextual cues and expectations that create nonspecific treatment effects. It is the sum of what’s happened to your biology, and those nonspecific effects that give you the end result.
That is part of the reason why one person might respond to one thing, and another person responds to something else. Or you respond on one day to something, and then you don’t respond to it on another day. These may be small variances, but it is interesting to see that this has been clinically shown to affect treatment response.
Factors shown to influence the outcome or your response to treatment can be divided in to three categories. These factors:
- Relate to the patient
- Relate to the health practitioner
- Relate to the treatment
For example, we know that if a treatment is more invasive, the individual is more likely to get a positive non-specific response. Taking a tablet works better than using a cream, having an injection works better than taking a tablet. Things like the appearance of the tablets also makes a difference.
An interesting study gave people red tablets versus blue tablets – neither colour tablet had any active medicine in it. The blue tablets made people sleepy, while the red tablets gave people more energy. There are other things like the cost that can also influence outcome – if something’s more expensive, there can be an expectation that is more likely to work.
Then there are factors that relate to you as the patient that also affect the placebo response. There may be things that affect your desired outcome, for example, if you really want something to work, it may be more likely to work. It could be that you have a memory of something working in the past and that makes it more likely to work for you in the future. If you’re really anxious about something, that feeling can interfere with the treatment effects too.
Finally, there are a number of factors related to the health practitioner that affect response. Interestingly, what your health practitioner is wearing can influence the way you respond to the medicine. Much of this is probably linked to the relationship that you actually have with that person. If that practitioner is persuasive, has a positive attitude about your treatment then you are more likely to have a trusting relationship, and you’re probably more likely to spend more time in the consultation. If you have a good relationship then you’re more likely to get a better outcome from the treatment the recommend. This highlights the important of having a good relationship with your health professional, as if you feel they care about you, you are more likely to have a better outcome from your treatment.
There’s also crossover between some of the other factors. For example if your health practitioner believes in the treatment that they’re giving you, it’s more likely to work for you.
In the middle of the matrix shown above is your expectation and verbal cues. This can be seen as the sum of your expectations around what’s going to happen with that medicine. Some factors you can change and others you cannot.
Headache diaries are essential for diagnosis, monitoring your symptoms and assisting in finding the most effective treatment for you.
There are paper versions and electronic ones easily accessible by your mobile phone. You can simply put in a few quick details when you experience a headache and receive a monthly report to track and discover triggers.
There are versions of printable headache diaries available on the NPS website mentioned earlier and also on Headache Australia website. https://headacheaustralia.org.au/headache-management/headache-migraine-diaries/
Migraine Buddy has been recognized as one of the best apps for tracking migraine and for reporting.
There are many different types of headaches and even within those headache subtypes, there is huge variability in everyone’s experience and responses to different headache treatments. There are many different treatment options available over the counter and on prescription. It’s really about trialing different options and working with your health professional to find the best fit for you.
There are some natural products with evidence behind them that may offer a benefit. Remember that natural does not necessarily mean safe and it is important to discuss those risks and weigh them against the benefits in your individual situation. You may need to try a lot of different things to work out what’s going to work best for you and it is always important to do that in consultation with a health professional.
Thank you to Cheyne Sullivan, Senior Medication Safety Pharmacist at Royal Adelaide who helped in preparing the visuals and slides for this information.