Dihydropyridine calcium channel blockers for Raynaud's syndrome (cold, blanched fingers/toes) diving in cold water

[Barryattle]

I'm posting this because I think it could help a lot of people and my search didn't really turn up anything on ScubaBoard addressing this directly.

I'm a doc who dives, but not a diving medicine doc. I have Raynaud's syndrome (fingers and toes turn cold, numb, dead white, and useless when cold) and had worried when I started diving (in the PNW) that it would stop me from diving. Dry gloves with 2 insulating gloves helped some, but I often came up with numb, useless fingers (and toes). As a doc, I knew that dihydropyridine calcium channel blockers (e.g., amlodipine, nifedipine, felodipine - generally used for high blood pressure and/or angina) often are helpful as they can prevent smooth muscle spasm that causes the small arteries to clamp down too much. For me, it is a night-and-day difference - I just take 1 dose several hours before diving. Yes, I still overinsulate a bit to prevent my core from getting cold (which can trigger attacks), but no more ending up with dead, useless fingers. (I also use it if I am going to go skiing and, for a day, I feel like a normal person with warm fingers and toes.)

I have recommended several divers to ask their docs for a prescription when this has come up in conversation and have gotten very positive feedback about the results. But I am puzzled that almost nobody seems aware of this treatment, or even that the problem is often treatable. So, unless the Duke folks jump in to say that, for some reason I am not aware of, this could be dangerous, I thought it deserved a thread here to make it easier for folks to find this information and maybe make their diving much more enjoyable, and safer.

 

[lowflyer]

Retired rheumatologist.
Many people are aware Calcium Chanel Blockers are a recognized treatment for Raynaud's, amlodipine being a favorite. Without going into a long treatise, some people should not take CCBs, such as those with GI dysmotility, pulmonary hypertension and, of course, LOW BP, etc. Arguably, potentially dropping a person's BP while diving by taking a CCB would not be recommended. So, not surprising that amlodipine is helping you.
PDE5 inhibitors have been used, Viagra being an example.
Etc.

 

[Sascha314]

My wife did not pass the medical exam due to that syndrom. Well the dive doctor said in warm countries its ok, but with our cold water situation its not.

The reason is, that you cannot fully control your fingers, so you might not be a le to control your bcd anymore. Even worse if you need to help your buddy. But she has it rather severly (for instance blue fingers and reduced movability outside if its sunny and 23°C but its windy)

How long do these drugs work? Not that you get an issue during a dive.

 

[Duke Dive Medicine]

I'm posting this because I think it could help a lot of people and my search didn't really turn up anything on ScubaBoard addressing this directly.

I'm a doc who dives, but not a diving medicine doc. I have Raynaud's syndrome (fingers and toes turn cold, numb, dead white, and useless when cold) and had worried when I started diving (in the PNW) that it would stop me from diving. Dry gloves with 2 insulating gloves helped some, but I often came up with numb, useless fingers (and toes). As a doc, I knew that dihydropyridine calcium channel blockers (e.g., amlodipine, nifedipine, felodipine - generally used for high blood pressure and/or angina) often are helpful as they can prevent smooth muscle spasm that causes the small arteries to clamp down too much. For me, it is a night-and-day difference - I just take 1 dose several hours before diving. Yes, I still overinsulate a bit to prevent my core from getting cold (which can trigger attacks), but no more ending up with dead, useless fingers. (I also use it if I am going to go skiing and, for a day, I feel like a normal person with warm fingers and toes.)

I have recommended several divers to ask their docs for a prescription when this has come up in conversation and have gotten very positive feedback about the results. But I am puzzled that almost nobody seems aware of this treatment, or even that the problem is often treatable. So, unless the Duke folks jump in to say that, for some reason I am not aware of, this could be dangerous, I thought it deserved a thread here to make it easier for folks to find this information and maybe make their diving much more enjoyable, and safer.

Not much to add to what @lowflyer said; his knowledge would be more specific than mine. If it works for you and there are no ill effects, awesome! What medication do you use, and at what dose?

Best regards,
DDM

 

[Barryattle]

Not much to add to what @lowflyer said; his knowledge would be more specific than mine. If it works for you and there are no ill effects, awesome! What medication do you use, and at what dose?

Best regards,
DDM

Agree with @lowflyer about contraindications, though I think for most, lowering BP a little is unlikely to cause any issues. One could try a dose on land for a day first and see if it causes problems. (Sustained use can cause lower leg swelling, a known, fairly common side-effect, but not a concern with single, occasional doses.)

I have used medium-high dose of CCBs (10 mg. amlodipine, 60-90 mg [sustained-release] nifedipine) as the evidence is they are more effective for Raynaud's than low dose. @Sascha314, the benefit lasts for pretty much a full day, so no risk of wearing off during a dive.

I haven't tried a PDE5 inhibitor as CCBs work well for me, but they are sometimes used to treat Raynaud's so might work if a CCB doesn't or causes problems. Topical nitroglycerin paste is also used as a Raynaud's treatment. I tried it but got no benefit.

I think the vast majority of divers with Raynaud's can safely take a CCB and hope this information helps them dive more comfortably (and safely).

 

[Vicko]

CCB have been used in freediving as a (not really legal) performance enhancers. They delay and reduce the loss of motor control that comes before a blackout. Lower BP also effects o2 consumption and reduces recovery times between dives. Most of the extreme static records were done while high, or low I guess, on CCB and beta blockers.

Wonder if they are beneficial in some way for scuba diving.

 

[Ryan Neely]

This is an interesting topic. I've been diagnosed with Raynaud's since going through chemo some sixteen years ago, though my symptoms are not nearly as severe as what has been described here.

We live in northern Minnesota and put in about twenty-five local dives each season. I've been fine with doubling up my gloves (in fact, I wear one full finger glove line and layer it with a thicker fingerless glove).

I had no idea the symptoms of Raynaud's became that severe. That's good to know so I can continue to monitor my own symptoms. Thanks for the info!

 

[crofrog]

I don’t have Raynauds but do have arthritis in my hands that get much worse with cold. The Santi heated gloves make life much much nicer and greatly reduce pain post dive.