This is because of national guidance introduced in 2018 to reduce the amount of money the NHS spends on prescriptions for treating minor conditions that usually get better on their own.
This includes prescriptions for a range of minor health concerns, including:
- Self-limiting conditions (will heal or be cured without treatment)
- Conditions which lend themselves to self-care (don’t usually require medical advice)
- Some vitamins, minerals or probiotics
There is more information here.
