Reaction to AZ vaccine, GP wants 2nd dose to be Pfizer

[Kittypillar]

Had my 1st dose of AZ back in March. Seems it didn't agree with me and about 10 minutes afterwards I had a reaction (swelling in my throat, went very wheezy and for nearly a week afterwards felt like I was trying to swallow a golf ball). Antihistamines did help and otherwise didn't have any other of the usual side effects except for a bit of a fever and feeling shivery.

Having spoken to my GP about it at the time and them having consulted the allergy service, I've now found out they are recommending my second dose be Pfizer instead, as they're worried second time round the reaction could be worse.

Unsure of how I feel to be honest - I'd obviously not want to have the same reaction (or worse!) again but it seems to be frequently described as "optimal" to have the same type of vaccine for both. Digging around on the internet for factual information on how it might effect efficacy and can't find anything that isn't speculation... Am I just not looking hard enough, can anyone signpost me to the something valid (I know other countries are mixing dose so surely there should be data to support that?)... Or do I just need to go with what my GP says and wait for the results from the studies going on right now to find out? Also waiting for a call back from my doctor (I found this out as got a call from the vaccine booking service) but wondered if anyone here could help in the meantime.

Thank you @MRex, definitely will do that.

@Peppapeg

The research coming out now suggests that mixing doses is looking like it's safe and effective, I am surprised though they'd recommend Pfizer given that people with allergies have widely been advised to have AZ.

This is making me feel uneasy. Whatever reaction I had would probably be considered mild I'm sure, but it does worry me that that's the recommendation they've come to without knowing why exactly it happened.

Throat swelling is classed as an anaphylactic reaction and should be taken very seriously and really treated with adrenaline. Allergies are funny things because they can present differently each time you react and get worse with each contact with the allergen. They are also poorly understood. Reactions have been noted with Pfizer too so I would not do anything until you’ve spoken with a specialist.

@Peppapeg

The research coming out now suggests that mixing doses is looking like it's safe and effective, I am surprised though they'd recommend Pfizer given that people with allergies have widely been advised to have AZ.

That was the initial guidance but it was a reactive policy based on 2 cases of anaphylaxis and that advice has changed.

AZ and Pfizer both contain potential allergens. Very rare to be allergic to these excipients (that's one reason they use them) but a few unfortunate people are.

@Kittypillar my throat didn't swell up- it just felt like it had been cheese-grated.

Thank you to everyone who has been so helpful, I really appreciate your input. I'll definitely be pushing for some sort of investigation if that's possible. I feel a bit miffed that this happened back in March and I've just been told the recommendation from the allergy service at pretty much the eleventh hour.