Rapid Access Headache Clinic Details
Dr O’Sullivan is a member of the International Headache Society, and has expertise in the management of headaches including the use of Greater Occipital Nerve block injections, Botulinum Toxin Injections, CGRP-related treatments and the provision of in-patient therapies including dihydroergotamine infusions. He has published peer-reviewed research papers on
headache, and has an ongoing research interest in the epidemiology, treatment and outcomes in headache.
Dr O’Sullivan has established a dedicated Headache/Migraine clinic in order to facilitate the prompt assessment, investigation and treatments for people with headaches. This clinic allows expedited access to investigations (if required), including brain imaging investigations such as MRI scanning, CT scanning, or other tests including blood tests, lumbar puncture or EEG.
If you would like an appointment to be seen in Dr O’Sullivan’s Headache/Migraine clinic, please ask your GP to send a referral to us.
Headaches are the most common neurological disorder, and it is estimated that
between 60 to 75% of adults have at least one headache per year.
Not only can headaches be a cause of disability, they can also be a huge source
of worry for many people. Concerns about brain tumours, meningitis or brain
haemorrhages feature prominently amongst the reasons why many people
attend their doctors initially. Indicators of sinister headaches are new sudden
onset headaches and associated features such as weight loss or fever. All
patients with new onset headaches should have a full neurological assessment
to exclude serious underlying conditions. However, it is important to realise that it
is only a very small minority of headaches that relate to these life-threatening
Many headache sufferers are never correctly diagnosed and therefore, may not
be receiving appropriate treatment – especially in the case of frequent
Types of Headaches
A headache is classified as ‘primary’ if there is not a structural abnormality (such as a
tumour) or another clear trigger for it such as a head injury. Primary headache disorders
are much more common than secondary headache disorders. The most common primary
headache conditions are migraines and tension type headaches.
Tension-type headache is the most common headache disorder, but it is usually mild and
generally only prompts medical consultation when chronic. Migraine is the most common
headache problem that causes patients to seek medical help.
Tension headaches usually last from between 30 min to 7 days. The pain has a
pressing/tightening quality, tends to be less severe than migraine, affecting both
sides of the head, and usually not aggravated by routine physical activity.
Vomiting is not seen with tension headaches, and nausea, or discomfort with
regular lights and sounds are uncommon. There can sometimes be an overlap
between migraine and tension headaches, and many people who attend my
clinic with headaches often have had more typical migraine headaches
previously but, with time, these have also developed some features of tension
Migraine headaches are usually one-sided, severe throbbing headaches with
accompanying nausea. The discomfort is worsened by bright light and loud noise. They
can last anywhere between four hours and three days and the headache needn’t be the
most troublesome symptom. People can feel unusual for hours to days before the
headache, with mood changes, fatigue, yawning, food cravings often described. The pain
of migraine can be accompanied by other features such as impairment of concentration,
and a feeling of faintness. Following the headache, the patient may still feel tired, washed
out, and irritable.
About 2/3rd of people with migraine do not get an aura. Migraine auras are
neurologic symptoms that usually precede the headache, lasting in general less
than 60 min. Visual symptoms are the most common, such as zigzag lines,
blobs, distortions is shape and size. Sensation changes or other disturbances
can also occur.
If you have had a headache associated with a feeling of nausea; were troubled by bright
light; and the symptoms limited your ability to work; then you probably had a migraine.
Medication Overuse Headaches
Medication-overuse headaches are usually characterised by a chronic daily headache.
Medication-overuse is the most common cause of ‘secondary’ headache and often
presents in combination with migraines, or mild head or neck injury.
In this scenario, taking regular painkillers of any sort may actually be causing the
headache to persist and get worse. This can be a huge challenge for people,
particularly as their doctors will ask them to significantly reduce and ideally stop
any regular painkillers.
Acute pharmacological treatments for headaches may include medicines such as
paracetamol, non-steroidal anti-inflammatory drugs (NSAIDs), triptans. However,
it is important to be aware that the frequent use of any painkillers can increase
the risk of chronic headaches and medication overuse headaches.
To help reduce the risk of developing a medication overuse headache, and to
break the vicious cycle of chronic headaches, Dr O’Sullivan will often recommend
lifestyle changes and prescribe headache preventer medications. Typical lifestyle
changes may involve reducing caffeine and alcohol intake, stopping smoking,
moderating caffeine, minimising stress and taking regular exercise. Riboflavin
and other supplements can also be helpful for some people. Headache diaries or
apps can often be helpful in identifying triggers for headaches, as well as
identifying whether various treatments are effective over time.
Oral tablet medications that can help prevent headaches include Propranolol,
Amitriptyline, Topirimate, Flunarizine. It is important to note that it often takes a
month to increase these medications to the correct amounts, and that any
prophylactic oral medication should be taken for at least 6 weeks at maximum
tolerated dose before deciding whether it is ineffective or not.
Non-tablet headache preventative treatments include injections or intravenous
Dr O’Sullivan regularly administers a Greater Occipital Nerve block to people
attending his Headache Clinic, which involves the injection of a steroid and
anaesthetic into the back of the head.
Dr O’Sullivan has undergone formal training in the injection of Botulinum Toxin
for neurological disorders, and he regularly injects people with chronic migraine
with Botulinum Toxin in his clinic.
Other non-tablet headache preventative treatments often used by Dr O’Sullivan include the use of CGRP-related treatments including Aimovig (erenumab) and Ajovy (Fremanezumab) in addition to in-patient intravenous infusions of dihydroergotamine (DHE).