I have a lifetime on warfarin to look forward to. It is keeping me alive but it is such a pain. Not physically, but in terms of getting it, keeping its effects stable and the frequent visits to the anticoagulant clinic.

I started taking warfarin four years ago after having open heart surgery to replace my calcified aortic valve with a titanium one. The disadvantage of a mechanical valve is that blood clots can form on it thus the requirement to take an anticoagulant to reduce the risk. The only way I could have avoided this medication was by having a tissue valve. A tissue valve can last 10-20 years whilst a mechanical one can remain viable for 50,000 years. I’ll be long gone before that but there is no way I would want to have this surgery again. I got through it unscathed last time. I may not be so lucky next time.

But being on warfarin has had an impact on my life in a number of ways.

Firstly, getting the stuff in the first place. On a number of occasions I have been placed at risk due to behaviour of my GP surgery. This surgery has just come out of special measures. It had an improvement notice to address the way they treat patients on high risk medication. That would be me. I can’t tell you how many times my repeat prescription has been denied or ignored. I did complain. Things have improved but a couple of weeks ago I had to remind them that a repeat prescription was a week late. 

Warfarin works by  decreasing the body’s ability to form blood clots by blocking the formation of vitamin K dependent clotting factors.  The dose of warfarin  is largely determined by how much vitamin K is consumed in food. So my diet needs to be consistent. I can eat foods with high levels of vitamin K  but that consumption can’t vary too much. You have to become an expert on what foods contain high levels of vitamin K. As I say a pain.

There is one tragic account that is often cited in scientific papers of a woman on warfarin who decided to adopt a healthier diet by increasing the amount of green vegetables she ate. Within a few weeks she was dead from a blood clot. Her death would have been prevented if she had been monitored during those weeks.

So now to the blood testing. The amount of warfarin required is determined by a blood test called the international normalised ratio (INR). It measures how long it takes the blood to clot. For most of us on warfarin our blood needs to take 2-3 times longer  to clot than someone not on warfarin. Hence the range 2-3. If you are below range there is a risk of developing a clot. Too high there is the risk of a bleed.

In the last few weeks I have been below range requiring an increased dose of warfarin. But now I’m over warfarinised. So my dose has been adjusted slightly  but I continue with the frequent blood test until it stabilises. Theoretically I could be tested every three months but currently it is weekly. It did strike me that I’m fortunate to be in a job that accommodates this commitment. If I was still working as a midwife it would not be as easy to manage. The NHS is not set up for those of us that work. 

But it is not just food that can affect the amount of warfarin. Alcohol, other medication and exercise can also affect it. 

You can drink alcohol on warfarin but again it has to be consistent. Two to three units per day. I tend to drink all my units in one go. Not sensible. I can’t tell you how often I have woken up in a cold sweat thinking ‘I should not have had that last drink or two’. 

Warfarin is affected by other medication. When I was prescribed statins three years ago my GP didn’t give a thought to this. At the time I was unaware of how lucrative patients on statins are to a GPs salary. Maybe if he had been more concerned about my welfare and less about his wallet I would not have ended up being at risk of a bleed.

And then there is exercise. The more active you are the quicker warfarin is metabolised so the higher the dose required.  Just like food and alcohol it has to be consistent. I am very active. I train 4-5 times per week and take over 12,000 steps every day in my commute to work and walking the dog. I have yet to come across anyone that is on a higher dose than me. But I am comparing myself with a waiting room that has its fair share of wheelchair users. Unlike my food and alcohol consumption I’m very consistent where activity is concerned unless I’m on holiday or unwell. I was in Barcelona last week. I walked and drank a lot of sangria. This could explain why I am currently out of range. 

Finally, I can’t be as adventurous as I’d like. I have to be aware of potential injury. What could be a minor inconvenience for most could be catastrophic for someone on warfarin. On the anniversary of having OHS I did a Tough Mudder. This year I have signed up for Nuclear Races. Am I putting myself at risk? Who knows. But I still have a life to lead even if I’m stuck with a lifetime on warfarin.