Dispensing HCTZ in Sulfa Allergy

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Sparda29

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Has anyone cross-sensitivity with these drugs? This is the case we had in class:

CS comes to the pharmacy with a prescription for Lisinopril 10 mg. She is already on HCTZ 50 mg but isn't compliant with it due to having to wake up multiple times to pee. Her current BP is 160/96. She is also on naproxen, cetirizine, loratidine, pseudoephedrine, and has a sulfa allergy (she had hives when given Bactrim).

She was taking the naproxen for pain and no longer has pain. And she was taking the pseudoephedrine for nasal congestion but doesn't have that anymore.

The question in the case is, would you fill the lisinopril prescription and what other changes would you make?

My answer is that I wouldn't fill the lisinopril, I would discontinue the HCTZ because of the sulfa allergy , discontinue either the loratidine or cetirizine based on what the patient says is more effective for allergies, and discontinue the pseudoephedrine and naproxen since they are unnecessary.

As for the blood pressure medication, I'd recommend to the prescriber to use either a beta-blocker or a calcium channel inhibitor.

What do you guys think?

The professor's answer was that she would reduce the dosage of the HCTZ to 25 mg, and fill the lisinopril.

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If she has been taking the HCTZ with no problem...there is not need to d/c it. There are no additional benefits in doses higher than 25mg fo HCTZ. Since her BP is uncontrolled, I would up the lisinopril dose.
 
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Since she has stage 2 hypertension, she needs to be on combo therapy (per JNC-VII guidelines). I would fill the lisinopril and yes, probably decrease her HCTZ to 25 mg. If she actually is compliant with these two, there should be some results in blood pressure lowering.

I don't think the allergy matters here. She has been taking the HCTZ and hasn't reported any problems with hives/ swelling, etc. I would just educate on symptoms of allergic reactions.
 
I think that interaction is listed because of the fact that some cough/cold meds have things that can worsen hypertension (PSE, etc). If there is a true drug interaction, I doubt it would be serious. Loratadine is one of the best tolerated things on the market and has few if any drug interactions. Not sure about the Zyrtec though.

If she took the diuretic in the morning, especially with a lower dose, it shouldn't keep her up all night.
 
i still dont understand why you would not fill the lisinopril. why d/c the HCTZ? the pt has not had any problems with the HCTZ in terms of allergy. As for the peeing, when is she taking the HCTZ? Hopefully the morning...adding the lisinopril and decreasing the HCTZ seems appropriate. or just add a combo lisinopril/HCTZ.
 
Go look at the sulfamethoxazole molecule and look at the HCTZ molecule...and tell me...do you think that it is likely there would be any cross-sensitivities KNOWING that the stereochemical arrangement of molecules is what drives the likelihood of one's immune system going ape**** at the presence of a xenobiotic?

My answer would be:
I would tell the patient to stop whining and take the damned HCTZ. It is the 1st line treatment for HTN. I'd fill the lisinopril, too.

You need to add something because she's at stage II HTN. Go read JNC 7. And I disagree with the professor for instantly wanting to decrease the dose. How the hell should I know how compliant they are based on that ****? You need more information. Do they take it 6 times a week or 1 time a month? If they never take it, I guess you might want to lower the dose of the thiazide...but if she does take it the vast majority of the time, then I'd just add the lisinopril. Of course she won't take the thiazide, so in reality, you'd change that, too. Maybe add a CCB.

Oh. And don't forget the lifestyle modifications that the magical drugs have made irrelevant and nobody ever does...because the drugs exist...

Oh, and asides from the sulfa relation to HCTZ, the stuff makes her pee, so I'm trying to avoid the diuresis.

What the hell did the patient expect? It's a diuretic. Thank God I work in a hospital where patients are force fed meds and don't whine...
 
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Looking at my drug cards, it says avoid cough, cold, allergy medications, with lisinopril. She's on the loratidine/cetirizine. Oh, and asides from the sulfa relation to HCTZ, the stuff makes her pee, so I'm trying to avoid the diuresis.


Come on.....think before you type. Nothing in this paragraph tells me you have learned any critical thinking in pharmacy school so far...look into this further!;)
 
Come on.....think before you type. Nothing in this paragraph tells me you have learned any critical thinking in pharmacy school so far...look into this further!;)
Yeah, with RPh's like this it's no wonder why we get no respect from people especially physicians. The original post is a disgrace to the profession of pharmacy.
 
Depending on how long she has been on pseudoephedrine that would play a role in her elevated BP as well...Use cetirizine or loratidine prn...After DC'ing PSE monitor BP and then decide on lisinopril..If still stage 2 add lisinopril and decrease HCTZ to 25mg
 
Tell me about the sulfa allergy.

Does it mean drugs with Sulfur will cause an allergic reaction? Then how about Morphine Sulfate?
 
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Good question, Stavi!

WVU, I disagree with not reducing the HCTZ. The more potent diuresis is a problem for the pt - in HTN, it's better to use multiple agents below their max doses rather than maxing the dose of one agent because maxing doses just gives you more side effects without more effective BP lowering.
 
Good question, Stavi!

WVU, I disagree with not reducing the HCTZ. The more potent diuresis is a problem for the pt - in HTN, it's better to use multiple agents below their max doses rather than maxing the dose of one agent because maxing doses just gives you more side effects without more effective BP lowering.

Yeah...but what if they have been only occasionally non-compliant and they legitimately need that much drug for their individual pharmacodynamics? Like I said...I need more information.
 
Not drugs with sulfur. Drugs with the sulfonamide moiety.

Correct!

If there is an allergy, and the pt has been taking that drug without demonstrating an allergic reaction, what do you do?
 
Yeah...but what if they have been only occasionally non-compliant and they legitimately need that much drug for their individual pharmacodynamics? Like I said...I need more information.

MAYBE there's individual pharmacodynamics, but what I would more likely think is the doc increased the HCTZ to 50mg due to inadequate BP lowering, and it would be more appropriate to add another agent when you get to 25 mg.

I mean, how much do you see 50 mg HCTZ any more? I used to see it lots when I first started practising, um, 23 years ago, and the pts required K supplements, and this was before PPIs so there were GI problems.

Dropping to 25 mg seems reasonable to me because the pt doesn't tolerate the 50 mg, and adding lisinopril is totally JNC 7.
 
I'm curious why you would d/c drugs without having an idea of why they are taking it and how often they take the drugs? What happens if she has significant DJD are you just going to leave her without pain meds?

As the others have mentioned JNC7 will basically help you get some of the information, but it seems there are several other wholes that should be probed before making a decission.

All that said, while I agree that HCTZ is likely a culprit in the diuresis, I'd probably also see about doing a quicky fingerstick just to make sure she's not diabetic.

Either way, with the information given, you are at a severe disadvantage, there's not enough to be able to cover a lot of the basic questions I have, but I agree that dropping HCTZ to 25 and starting the lisinopril are reasonable starts, unless she's elderly then I think that lisinopril 10 too high, but mostly because I've experience a LOL (little old lady) starting that dose then having a ton of falls.
 
I'm curious why you would d/c drugs without having an idea of why they are taking it and how often they take the drugs? What happens if she has significant DJD are you just going to leave her without pain meds?

As the others have mentioned JNC7 will basically help you get some of the information, but it seems there are several other wholes that should be probed before making a decission.

All that said, while I agree that HCTZ is likely a culprit in the diuresis, I'd probably also see about doing a quicky fingerstick just to make sure she's not diabetic.

Either way, with the information given, you are at a severe disadvantage, there's not enough to be able to cover a lot of the basic questions I have, but I agree that dropping HCTZ to 25 and starting the lisinopril are reasonable starts, unless she's elderly then I think that lisinopril 10 too high, but mostly because I've experience a LOL (little old lady) starting that dose then having a ton of falls.

Naproxen has a potential of reducing the therapeutic abilities of HCTZ and Lisinopril, which is why I'm suggesting that it be discontinued.
 
Naproxen has a potential of reducing the therapeutic abilities of HCTZ and Lisinopril, which is why I'm suggesting that it be discontinued.

Somewhat off the topic, but that's not the main problem when you combine NSAIDs with diuresis and ACE-I, especially if its a patient with long-standing and uncontrolled hypertension (and who knows what else, in this case).

Right answer, wrong question.
 
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and what would make you think it is needed to D/C the HCTZ becasue she has a self reported allergy to "sulfa". I wish I could stop everyone's lortab becasue they told me they had an allergy to T+C #3, it'd be my dream
 
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and what would make you think it is needed to D/C the HCTZ becasue she has a self reported allergy to "sulfa". I wish I could stop everyone's lortab becasue they told me they had an allergy to T+C #3, it'd be my dream

For the sake of this case, it's not a self-reported allergy. It was a documented allergy that she broke out in hives due to the Bactrim.
 
Looking at my drug cards, it says avoid cough, cold, allergy medications, with lisinopril. She's on the loratidine/cetirizine. Oh, and asides from the sulfa relation to HCTZ, the stuff makes her pee, so I'm trying to avoid the diuresis.

You are reading, not thinking.

1. allergy medications, with lisinopril...really?
2. sulfa relation to HCTZ...I thought it was with Bactrim?
3. the stuff makes her pee...what other effect are you expecting?
 
You are reading, not thinking.

1. allergy medications, with lisinopril...really?
2. sulfa relation to HCTZ...I thought it was with Bactrim?
3. the stuff makes her pee...what other effect are you expecting?

#2 - She had the reaction to Bactrim. Hence, she has an allergy to the sulfonamide moiety. HCTZ has the sulfonamide moiety.

#3 - Perhaps we can change it to AM so she doesn't wake up to pee, however if HCTZ is still a sulfonamide.

The whole point of my thread was if people have seen a whole lot of allergies to HCTZ due to a sulfa-allergy.
 
Naproxen has a potential of reducing the therapeutic abilities of HCTZ and Lisinopril, which is why I'm suggesting that it be discontinued.

You still missed the bigger picture, people generally don't take naproxen just for kicks. Before you blanket d/c the medication you need to see how and why she takes it and THEN decide how to approach solving that problem. You should have a lot of questions floating in your head at this point, since the information was sparse.
 
#2 - She had the reaction to Bactrim. Hence, she has an allergy to the sulfonamide moiety. HCTZ has the sulfonamide moiety.

#3 - Perhaps we can change it to AM so she doesn't wake up to pee, however if HCTZ is still a sulfonamide.

The whole point of my thread was if people have seen a whole lot of allergies to HCTZ due to a sulfa-allergy.

If both have sulfonamide moeities and that is her allergy, then how do you explain her having the reaction with Bactrim and not HCTZ?
 
Nope, never seen it. I'll usually just counsel the pt on what to watch for. Every time I've called the doctor, I've been laughed off the phone.
 
You still missed the bigger picture, people generally don't take naproxen just for kicks. Before you blanket d/c the medication you need to see how and why she takes it and THEN decide how to approach solving that problem. You should have a lot of questions floating in your head at this point, since the information was sparse.

She was taking it for post-op knee pain which is now gone. The professor also agreed with taking her off the Naproxen.
 
She was taking it for post-op knee pain which is now gone. The professor also agreed with taking her off the Naproxen.

So how much more of the case did you leave off?
 
#2 - She had the reaction to Bactrim. Hence, she has an allergy to the sulfonamide moiety. HCTZ has the sulfonamide moiety.

Survey Says:

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You need to go stare at some molecules...or get a better understanding of how physical stereochemical structure affects IgE mediated reactions.
 
Survey Says:

x.jpg


You need to go stare at some molecules...or get a better understanding of how physical stereochemical structure affects IgE mediated reactions.
this is probably the best rejection post I have seen in a very long time. Very very creative.
 
Naproxen has a potential of reducing the therapeutic abilities of HCTZ and Lisinopril, which is why I'm suggesting that it be discontinued.

This is partly right. NSAIDs can cause retention and therefore, would increase BP. Even if the patient is not on HCTZ and lisinopril, d/c naproxen is recommended esp in this case since the patient doesnt need it anymore.
 
If both have sulfonamide moeities and that is her allergy, then how do you explain her having the reaction with Bactrim and not HCTZ?


You have to go to your med chem for this one. Sulfa antibiotics all have an arylamine group which isn't present on non-abx sulfonamide drugs. It is purported that this may be the reason there isn't a cross sensitivity between the two. If you look at the research, there is a higher rate of cross sensitivity between sulfa abx and penicillins than between sulfa abx and sulfa non-abx and also between penicillins and cephalosporins. Since Hives is a type I hypersensitivity reaction, if the patient presented initially with a script for HCTZ, I would warn the patient and consult the doctor of the low, but possible, risk and document this and fill it if there are no objections from the patient or doctor. As for the lisinopril, you need to get her to stop the Pseudoephedrine. It is an alpha agonist which causes vasoconstriction. There is nothing wrong with the antihistamines but i would question why she is on two.
 
OK so this is my understanding and hopefully someone can back me up
If a patient has a "sulfa allergy" and has a script for HCTZ

And it was JUST A RASH (ie. minor):
Then go ahead and fill it (w/o calling the doc/documenting)...no big deal cuz of the low/barely any risk of cross sensitivity

If it was an ANAPHYLACTIC reaction (difficulty breathing etc.) then do NOT fill it w/o calling the doc and documenting because you want to be extra careful even though you know everything is probably cool
 
OK so this is my understanding and hopefully someone can back me up
If a patient has a "sulfa allergy" and has a script for HCTZ

And it was JUST A RASH (ie. minor):
Then go ahead and fill it (w/o calling the doc/documenting)...no big deal cuz of the low/barely any risk of cross sensitivity

If it was an ANAPHYLACTIC reaction (difficulty breathing etc.) then do NOT fill it w/o calling the doc and documenting because you want to be extra careful even though you know everything is probably cool

The important part of the case was the Pt was already on HCTZ w/o complaint or S/S of allergy. Sparda was considering whether or not to D/C tolerated HCTZ based on his DUR and observation of documented Bactrim reaction. Then everyone smacked him around a bit.
 
I'd think she'd be on 25 mg BID rather than 50 mg qam, but something to look into. Also as mentioned, when is she taking the HCTZ, is it PM or AM. My mother in law was taking zestoretic qam but was noticing the diuresis didn't hit til pm. They told her to try qpm to see if they 12 hour time difference helped.
 
The important part of the case was the Pt was already on HCTZ w/o complaint or S/S of allergy. Sparda was considering whether or not to D/C tolerated HCTZ based on his DUR and observation of documented Bactrim reaction. Then everyone smacked him around a bit.


yea my scenario was separate from the original. I was curious if people agreed with me
 
[ There are no additional benefits in doses higher than 25mg fo HCTZ [/quote]

Is this really true? why is there a 50 mg then...
 
If you're getting at the fact that HCTZ 50mg has no efficacy over 25mg while Zocor 80mg does over 40mg, the sure.

That wasn't my point however.
Are you talking about drugs going to market with multiple, unnecessary manipulations in strengths in order to sell more of a drug due to multiple strengths being available (without necessarily having solid proof of efficacy at all strengths)?... patent extensions, blah, blah, blah... my head hurts... excuse me if I sound "heady"...
 
If you're getting at the fact that HCTZ 50mg has no efficacy over 25mg while Zocor 80mg does over 40mg, the sure.

That wasn't my point however.

There used to be 100 mg HCTZ too. There is no reason to use anything more than 25mg of HCTZ. Thiazides have a flat dose response curve. There are reasons (not good ones mind you) to use Simvastatin 80mg. It's much harder to get a drug off the market once it's on the market....
 
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