Brief Answer:
It's available in UK as OTC but in US restricted due to side effects

Detailed Answer:
Hi! Thanks for sharing your concerns with us. We will try to help you in best way possible.

Based on the query you have asked, though it's available as OTC in many countries including UK but it has got potential of causing some serious side effects including heart vessels strains and hemoglobin and blood related side effects and either of these can be potentially serious, though common side effects like neurological including parasthesias etc are not that dangerous still due to the cardiac and marrow related issues it's use has been kept restricted in US and is left on the choice of the physicians choice to chose the patient to start with its therapy or not and that's made based usually in screening out heart patients or tendency to have increased probability to develop these side effects.

Other options like non steroidal anti inflammatory drugs etc can be used during acute attack as alternative in migraine and then based on prescription if long term use is advised it can be continued based on that prescription and chances of immediate change in this policy is still not under discussion yet but in future it may be changed if data on safety profile is further studied by ongoing researches in medical field continously.

Hope this has answered your query, if you have any more questions, feel free to ask. Regards.

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