I've been in a position before where I couldn't afford to pay for my asthma inhalers. I'd had a pre-payment certificate but it had run out and I couldn't afford another one. My asthma was still out of control at that point and I'd been hospitalised several times after bad attacks. If I'd had another attack the cost to the NHS would've been far higher than the price of an inhaler.
I get free prescriptions atm so it's no longer an issue but ideally I'd like there to be a system where the asthma-related medication was free.