A total of 106 products are reported as being unavailable on the free drug shortages tracker compiled by GPonline's sister website MIMS. The list is not exhaustive - suggesting more are likely to be unavailable.
The drug tracker, which aims to help GPs avoid prescribing medicines that are currently unavailable, lists a further 50 drugs that have recently been out of stock, but are now back in pharmacies.
GP leaders say patients are being forced to 'chop and change' between medicines as commonly-prescribed drugs go out of stock, with availability changing 'almost by the week'.
BMA GP committee chair Dr Richard Vautrey told GPonline that medicines shortages were getting worse and causing 'no end of problems' for practices and patients.
The Leeds GP said practices were facing additional workload because patients were 'frequently' being forced to come back following appointments to request an alternative prescription.
'It is having a serious impact. There is real uncertainty over whether common medicines are going to be available, and patients may have to return to their practice to get an alternative prescription, or go round lots of pharmacists looking for one that has a particular drug in stock.'
The GPC chair warned that practices were often not confident about prescribing alternatives because local pharmacies 'may not have the alternative either'.
'This is happening frequently and getting worse - patients are chopping and changing between products,' he said. 'Their condition is usually managed by the alternative, but we are finding this is something that changes almost by the week, it is very difficult to keep track.'
Dr Vautrey called for 'far more honesty and openness about why it is happening and what the government is doing to resolve it'.
The GPC is sending out updates to BMA members on drug shortages, but Dr Vautrey said this 'shouldn’t be necessary'. He said: 'In every other walk of life you get regular supplies of products - we need the government to be taking much firmer action with pharma companies and wholesalers, and to provide a real explanation of what is happening and what they are going to do to stop it.
'It causes a whole degree of uncertainty and frustration that the government is focused so much on Brexit at the expense of everything else.'
Warnings over the rise in drug shortages across the UK come just a week after an online pharmacy published a list of around 60 products that pharmaceutical suppliers have predicted could become more expensive or difficult to obtain in the event of a no-deal Brexit.
Manufacturers revealed last month that GPs may need to switch women to alternative HRT products because of looming problems with availability of several widely-prescribed therapies. The drug tracker lists a number of HRT drugs that are currently out of stock.
GPonline reported earlier this year that one in seven GPs had seen patients experience harm or slower recovery over the previous 12 months because shortages had forced them to switch to a second-choice drug.