Yesterday morning I went into something of a tailspin, as I realised I was going into a 4-day bank holiday without the major component of my COPD meds – Phyllocontin Continus (hereafter referred to as PC). I was also out of Co-codamol, but as I have an emergency stash of DHC that wasn’t much of a problem, other than DHC exacerbates my heart-related oedema, but I can get by on half a dose (30mg), plus a couple of Paracetamol, if I have to. Not fun, but doable.
So after a mini melt-down (surprising how fast depression can come rampaging out of nowhere with a little encouragement – OK now, though), I found a few PC tabs in my carry-pack (the A5-sized leather man-bag that goes everywhere with me and contains my inhalers and a selection of meds). Only a few, though – 4, to be precise. That’s a 25% dose for 4 days, taking one in the morning (normal dose 2 tabs (450mg), every 12 hours), and none at night.
That worked out OK yesterday though, of course, there was the residue of my full morning dose lingering in my system. Today is crunch time.
So far, so good, though. I feel bright, alert, my colour is good – for the past year or so I’ve been white and gaunt – and most important of all, the devastating nausea that greets me every single morning is absent. OK, there’s a little lurking in the background, but nothing compared to the normal horror show – think being seasick, combined with the very worst hangover you’ve ever had, and you won’t even come close. Yes, it really is that bad – every goddamned day.
So I went online in search of a side-effect list for PC, and the first thing… Hang on a minute – for those unfamiliar with PC its active ingredient is Aminophylline, which in turn is a combination of Theophylline and ethylenediamine, which renders the Theophylline more soluble in water. Theophylline is highly toxic, and the difference between therapeutic and toxic doses can be as little as 1mcg per ml – this is not a drug you want to get careless with. I can be quite cavalier with my meds, taking doses and combinations that suit me best. Not with PC though.
OK, on with the show…
So, as I was saying, I went online to look up the side effects, and the first thing I came upon was this cautionary note:-
Use with caution in
Irregular heartbeats (arrhythmias)
Much though I dislike the idea, at 67 the first category unavoidably includes me (inside every 67-year-old guy there’s a 40-y-o thinking wtf went wrong?!), while the other two are also a shoo-in for PC-related problems.
I won’t list all of the potential side-effects, there would be little point as they’re easily available online, just those that affect me:-
Most of the side effects of aminophylline (theophylline) have been dependent on serum concentrations. Generally, theophylline serum concentrations ranging from 10 to 20 mcg/mL are considered therapeutic, and serum concentrations greater than 20 mcg/mL are associated with greater toxicity.
There are several factors which may predispose a patient to higher serum concentrations and, thus, toxicity. These factors may include increased age, concomitant drugs which reduce the clearance of theophylline**, congestive heart failure,
Chronic overdosage is seen more commonly in older patients, and severe toxicity may occur with serum concentrations which are much lower than those seen in severe acute toxicity. In these patients, age is a predictor of severe toxicity.
**I’ve investigated this, the results for drugs I currently take are at the end.
Gastrointestinal side effects have included nausea, vomiting, and abdominal pain. Aminophylline may also cause locally-mediated gastrointestinal upset.
Nervous system side effects have included generalized seizures,
Theophylline serum concentrations are a significant predictor of arrhythmias. One study reported multifocal atrial tachycardia in 8% and 16% of patients with a serum concentration between 10 and 20 mcg/mL and greater than 20 mcg/mL, respectively. The onset of serious arrhythmias is not always preceded by less severe signs of theophylline toxicity.
Cardiovascular side effects have included increased heart rate which has progressed to atrial tachycardia or ventricular tachycardia. Patients with a history of arrhythmias may be predisposed to this effect.
Metabolic side effects have included hypokalemia, hyperglycemia,
Hypokalaemia (potassium deficiency), is a problem I’ve known about for years, and taken a supplement to counter. My heart drug, Candesartan, however, prohibits this as it tends to concentrate potassium. I remain unconvinced that it concentrates it enough to counter the deficiency caused by PC, but I seem to be the only one worried. Given how well I feel on just a fraction of my normal dose, I’m guessing I still need supplementation if taking the full quota of PC – but getting it wrong could cause very serious problems.
The trouble is, I can’t discuss any of this with my witless GP as his knee-jerk reaction is to stop prescribing, rather than to look at the problem in detail and find a work-around. My potassium levels need monitoring for a few weeks, and a safe level of supplementation figured out.
Not taking PC at all isn’t an option. I simply cannot get by on inhalers alone, even with my nebuliser, nor can I take plain Theophylline. I took that during the late 70s and every backpacking trip was punctuated by a trail of puke after my evening dose. It’s not a drug I will ever take again.
There are other benefits to reduced PC, at least in the short term. For most of my life, every day has started with severe, uncontrollable, coughing, but of late it’s gone on for hours. Now it’s absent. Also, one of the less charming aspects of COPD is expectorating gunk of varying degrees of foulness – now it’s clear and infection-free.
In recent months my memory has gone to hell. My short-term memory was trashed by ME years ago, but lately my memory as a whole has been defective, hence my newly-acquired habit of running out of meds. Now, though, I feel sharp and alert, and my mind has a clarity that it’s lacked for far too long.
There’s more, but you get the point – on minimal PC I’m greatly improved in many ways. But why?
Once again, I can’t talk to my GP about his as the prick will just stop prescribing, so I’ll have to work out the dose for myself, which will probably be half what I’ve been taking, 225mg, every 12 hours, PC tablets can’t be cut in half, as they’re sustained release tabs, a waxy matrix from which the drug is slowly released.
This tends to confuse hospital staff (are those I encounter selected for their stupidity?), and a ward sister once told me that because they are sustained release it didn’t matter that they were delivered to me hours late, which is the most egregious and downright dangerous bullshit. It is essential that blood plasma levels of the drug remain steady, and don’t fluctuate wildly, which means taking the tablets to a strict timetable, in my case every 12 hours. If, for any reason, I missed a dose, I was in trouble long before the next dose was due. I explained this – politely – to the sister, who flatly refused to believe me. It probably goes without saying that this was in Arrowe Park Hospital, Wirral, on the coronary ward.
It’s as if there’s something in the water at APH – it tastes bloody disgusting for a start – that causes staff to forget their training and embrace total bollocks, like the pharmacist who asked if I’d like to try a beta-blocker that “might not” harm/kill me! Beta-blockers are dangerous with asthma, they also conflict with beta-2 agonists, like Salbutamol (Ventolin), and Salmeterol (Serevent), both of which I take.
But I digress. Clearly, PC has become toxic on many levels, so the only sensible thing to do is reduce the dose. Last night I didn’t take any, and while I was very late getting to sleep, I did sleep very well, and for the first time in many months, I dreamed. Or, at least, remembered I’d dreamed – apparently we always do, whether we’re aware of it or not – it’s the brain’s way of clearing out the psychological debris that accumulates during the day (or, perhaps, given how much better I feel today, I really haven’t been dreaming, or not enough, anyway?).
In closing, don’t read this and start buggering about with your PC dose. Just don’t, OK? Do as I say, not as I do. If you choose to ignore this advice I accept no responsibility.
Furosemide: has reportedly increased, decreased, or not affected serum theophylline levels. The mechanism and clinical significance is unknown. Dosage adjustments may be required if an interaction is suspected.
Seriously? That’s an official interaction report? It’s bloody meaningless!
Ventolin: Concomitant use of a beta-2 adrenergic agonist with theophylline may result in additive risk and/or severity of hypokalemia and adverse cardiovascular effects such as palpitations, tachycardia, and blood pressure elevations. The interaction may be more likely when a systemic or nebulised formulation of the beta-2 agonist or a high dosage of theophylline is used. The resultant hypokalemia is often transient and not clinically significant; however, serious events including rare cases of cardiorespiratory arrest and intestinal pseudo-obstruction have been reported. In addition, since beta-2 agonists may sometimes cause QT interval prolongation, the development of hypokalemia may potentiate the risk of ventricular arrhythmias including torsade de pointes.
Patients should be advised to notify their physician if they experience worsening of their respiratory condition or potential signs and symptoms of hypokalemia such as fatigue, weakness, myalgia, muscle cramps, numbness, tingling, abdominal pain, constipation, palpitations, and irregular heartbeat.
In a nutshell, Ventolin and PC might well be screwing up my heart and my bowels. Since not taking Ventolin isn’t an option I would even consider for a moment, reducing PC is the only alternative. I don’t routinely take nebulised Ventolin – it’s only for emergencies.
And see that last section, in bold? I’ve been presenting with all those symptoms for almost 30 years – nobody bothered to mention that my meds were causing the problems, they told me I was imagining things or making it all up. Bastards. They were eventually all rolled up into the diagnosis – after 10 years – of ME/CFS.
That, of course, gives even more credibility to my feeling that I do not have, and have never had, ME/CFS (this, by the way, doesn’t affect my DLA – the diagnosis came very much later).
That’s all the listed interactions for my meds, so I ran a manual search for the rest and came up blank. Doesn’t mean there aren’t any, just not reported or figured out. Best I can do though.
I’ve also tried to find out if my memory problems are linked to PC, and the answer seems to be no, but getting a clear picture from the anecdotal evidence that’s out there is made impossible by the profound ignorance of the patient population (one reason for my publishing all the COPD info on here in the first place). It has occurred to me, though, that failing memory could be due to reduced blood flow caused by aortic valve stenosis, If so, I’m screwed.
All of the above data from Drugs.com (Links to PC side-effects page)