03.Are tablets making it worse?
Used appropriately, painkillers can be extremely helpful for people who have chronic headaches. But taking these medicines too often can backfire, resulting in more frequent and severe pain, perpetuating the problem.
The exact reason for this is unclear, but it’s believed that regular use of painkillers may alter the processing of pain signals in the brain, making you more sensitive to pain and affecting how your brain naturally deals with it. In response, you take more painkillers, and the cycle continues. After a while, your body becomes used to the presence of a certain level of the drug, and stopping it results in withdrawal – and more pain.
So-called medication overuse headache (MOH) can arise from taking as few as ten doses of painkillers for headaches in a month, depending on the individual and the type of painkiller used. Paracetamol, NSAIDs, codeine and triptans are all implicated. Interestingly if you’re taking painkillers for pain other than headache – such as osteoarthritis, say - you’re less likely to suffer the same MOH effect.
A diagnosis of MOH is made if the headaches occur on more than 15 days per month for at least three consecutive months, in conjunction with the regular use of painkillers. Depression and anxiety are commonly associated problems and may complicate treatment. At least one per cent of the population is estimated to suffer from MOH, and it’s now the third-most common headache after tension-type and migraine headaches.
The treatment of choice is complete withdrawal, under your doctor’s supervision. During this time, your headache often worsens before it gets better.
Apart from MOH, excessive use of painkillers may have other side effects:
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NSAIDs can irritate the stomach, causing gastrointestinal bleeding, heartburn, nausea or even ulcers. They can also cause kidney damage.
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Paracetamol poisoning from overdose causes jaundice, liver failure and death. What constitutes an overdose can vary from person to person – liver damage has been known to occur after a single dose of 14 regular tablets, but it can also be cumulative. Like NSAIDs, paracetamol can also cause kidney damage.
- The main side effects of painkillers containing codeine are constipation, drowsiness, dizziness and nausea. There’s also a possibility of addiction among long-term users ; the risk here is that increasing the dose to get more codeine may lead to paracetamol or NSAID poisoning. Addiction, abuse and recreational misuse of codeine led to it being rescheduled to pharmacist-only or prescription-only medicine in May 2010.