Prescriber 21(19): 5th October 2010

Long and very useful article on vestibular causes of dizziness. For starters, a useful breakdown into acute, recurrent acute, and chronic:

Acute

Vestibular neuritis aka vestibular neuronitis aka viral labyrinthitis (although turns out that last is inaccurate – labyrinthitis causes acute hearing loss and tinnitus as well as vertigo).

Labyrinthitis

Recurrent

Four common causes: BPPV, vestibular migraine, Meniere’s, and recurrent vestibular neuritis.  Also a host of rare ones, of which vestibular paroxysmia seemed worthy of brief note.

Chronic

The chronically dizzy/off-balance patient, describing him or herself as feeling drunk/walking on cotton wool/having cotton wool in head.  Usually a combination of a peripheral vestibular deficit and inadequate central combination.  May be multisystem.  Or, in plain English: I’m afraid it’s wear and tear of all the various systems that help you balance, Mrs Jones.

So.  Having classified those various types, what do we need to know about them all and what do we do about them?

Vestibular neuritis/labyrinthitis – First off, it’s important to remember that labyrinthitis can be caused by bacterial infection as well as viral.  This will cause severe hearing loss and vertigo and may be associated with acute otitis media and/or meningitis.  It’s specialist territory and, if it’s suspected, I should really be phoning the ENT team to get the patient seen urgently.  So, must remember to look for that. (There you go – looking in the ears of patients with vertigo isn’t just a formality to keep them happy, as I had often suspected.  It’s actually very important to exclude otitis media.)

For treatment there is, of course, cinnarizine and good old Stemetil.  But there are other options – promethazine, dimenhydrinate (now produced in combination with cinnarizine as Arlevert), cyclizine, and prednisolone (100 mg reduced to 10 mg over a period of three weeks).  Antiviral medication, despite this supposedly being viral in origin, doesn’t help, which makes me wonder whether we have any actual evidence for it being viral or whether this is just one of those catch-all we-don’t-know-so-we-call-it-a-virus things.

I already knew that medication shouldn’t be used long-term as it may actually delay recuperation, but have in the past been faced with the dilemma of what to do when being asked to sign a repeat prescription for someone who already is on Stemetil long-term for dizziness and who I know is likely to be somewhat unimpressed by a doctor they don’t know ringing up and advising them to stop it.  In such circumstances I admit to having taken the line of least resistance and signed the script, but it seems this was wrong (no shit, Sherlock) – prolonged use can often cause extrapyramidal side-effects.

BPPV – The good ol’ Epley manoeuvre, of course.  On which, this being a journal about medication, the article had nothing further to say.  (No worries – I know the Epley.)

Vestibular migraine – More common than previously realised (may affect as many as 1% of the population) and, despite the name, more often than not there’s no associated headache.  May last anything from minutes to days.  If there is associated migraine headache or aura, the diagnosis is easy, and a family history of migraine can raise suspicions, but how you’re supposed to distinguish it from Meniere’s or recurrent vestibular neuritis is still totally unclear to me.  As to what you do about it, lifestyle and dietary alterations (unspecified) may do the trick.  If not, treat acute attacks as you would any other migraine – analgesics, antiemetics, and possibly triptans (which are also one way to confirm the diagnosis).  Prophylactics listed are, in this order, amitriptyline/nortriptyline, propranolol, pizotifen, verapamil, (less effective but often well tolerated long-term), and, surprisingly, acetazolamide, which occasionally works due to its similarities with topiramate.

Meniere’s – Causes attacks lasting between 20 minutes and 10 hours, described as a build-up of unilateral tinnitus, aural fullness, and hearing loss, followed by severe vertigo with V&D, with hearing recovering to a variable degree after the attack.  Attacks can be clustered or spaced over months or years.  It can present with only one or two symptoms, which is particularly difficult to diagnose.  It might be autoimmune, but no-one really knows.

Restricting sodium to 2.5 g or less per day is often recommended though not supported by brilliant evidence.  Betahistine is usually first line medication, probably acting via vasodilation of the stria vascularis of the inner ear, thus reducing hydrops (which I suppose explains why it isn’t considered useful for other forms of vertigo), and via some degree of vestibular sedation.  It is extremely well tolerated.  Second choice is usually bendroflumethazide (again, supposedly reduces inner ear hydrops) and can work particularly well for women who get exacerbations with menstruation – try BFZ for the five days before menstruation.  Oral or transtympanic steroids can be of use, cinnarizine or Arlevert can help symptomatically, and transtympanic gentamycin shows marvellous promise as a new treatment, with a very high success rate (it can cause unilateral hearing loss, though).  And, interestingly, for patients who just want an attack-free day for a special or important occasion, 25 mg of urea will almost guarantee 24 hours free of attacks.  It tastes horrible, though, so the author recommends dissolving it in orange juice and drinking it quickly.  There has to be a women’s magazine headline in there, doesn’t there – ‘I Drank Wee To Make It Through My Wedding Day’.  You heard it here first.

Recurrent vestibular neuritis – Recurrent vertigo attacks lasting hours or days.  So, um, pretty much the same symptoms as most cases of vestibular migraine then – what the difference is meant to be or how you distinguish, I’m still not clear.  Thought to be due to reactivation of a virus, so there is a theoretical basis for treating each attack with aciclovir + prednisolone at onset.  This one was of interest to me as it sounds like the problem my mother-in-law gets, so perhaps that’s what she should try – must remember to mention it to her.

Vestibular paroxysmia – one of the less common causes of intermittent acute vertigo that seemed worthy of passing mention.  It presents with multiple very brief spins every day, is thought to arise from irritability of the vestibular nerve, and can be treated by carbamazepine.

Chronic vestibular symptoms – Much harder to deal with, and long-term medication better avoided as can prevent vestibular adaptation.  Look for any signs of neurological or cardiovascular red flags that might require referral.

The other big article of interest in this journal was on secondary prevention after an MI.  Aspirin, beta-blockers, ACE inhibitors and statins should be the mainstay, plus clopidogrel short-term (see below). ARBs are second-line for those who can’t tolerate ACEs, but shouldn’t be used otherwise as you don’t get any improvement on the effect of ACEs for all that extra money.  Rate-limiting CCBs may be an alternative to beta-blockers in patients without left ventricular dysfunction, but their benefit even in these patients is marginal and they do more harm than good in patients who do have LVD.  Eplerenone is helpful in patients with CCF or diabetes, in whom it reduces mortality by 2.3 %, but don’t forget to monitor electrolytes.

Clopidogrel is supposed to be used for a year after NSTEMI, unless you’re in Scotland where it’s only supposed to be used for three months.  Scotland bases this on the CURE and CHARISMA trials, both of which show dual antiplatelet therapy for more than three months after NSTEMI to be helpful only in subsets of patients and accompanied by a significant increase in bleeding risk.  Why NICE disagree with this is not clarified.  As for clopidogrel use after STEMI, we seem to be surprisingly short on evidence – SIGN and NICE both agree it should be used for four weeks, but nobody seems sure whether using it for longer helps.  In patients with drug-eluting stents, it should be used for a year after insertion, while patients with bare metal stents should take it for three months.

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About Dr Sarah

I'm a GP with a husband and two young children.
This entry was posted in Cardiovascular, ENT, Vertigo. Bookmark the permalink.

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