What happens if you eat moldy bread and have a penicillin allergy

Having a Penicillium mold allergy doesn't mean that you're allergic to the antibiotic penicillin.

What happens if you eat moldy bread and own a penicillin allergy

While penicillin was indeed originally developed from Penicillium mold, people with this specific mold allergy are not at any more risk of developing an allergy to this class of antibiotics than anyone else with a history of allergies.

Risk factors that make it more likely to own a penicillin allergy include:

  1. Having a history of allergies
  2. Being exposed to high or prolonged doses of penicillin
  3. Having had an allergic reaction to another helpful of drug
  4. Having a family history of drug allergy
  5. Having an infection such as human immunodeficiency virus (HIV) or Epstein-Barr virus, which can contribute to allergic drug reactions

Allergy to Penicillin Drugs


How to take antibiotics?

Take antibiotics as directed on the packet or the patient information leaflet that comes with the medicine, or as instructed by your GP or pharmacist.

Antibiotics can come as:

  1. tablets, capsules or a liquid that you drink – these can be used to treat most types of mild to moderate infections in the body
  2. creams, lotions, sprays and drops – these are often used to treat skin infections and eye or ear infections
  3. injections – these can be given as an injection or through a drip directly into the blood or muscle, and are used for more serious infections

Missing a dose of antibiotics

If you forget to take a dose of your antibiotics, take that dose as soon as you remember and then continue to take your course of antibiotics as normal.

But if it’s almost time for the next dose, skip the missed dose and continue your regular dosing schedule.

Do not take a double dose to make up for a missed one.

Accidentally taking an additional dose

There’s an increased risk of side effects if you take 2 doses closer together than recommended.

Accidentally taking 1 additional dose of your antibiotic is unlikely to cause you any serious harm.

But it will increase your chances of getting side effects, such as pain in your stomach, diarrhoea, and feeling or being sick.

If you accidentally take more than 1 additional dose of your antibiotic, are worried or you get severe side effects, speak to your GP or call NHS 111 as soon as possible.


When antibiotics are needed

Antibiotics may be used to treat bacterial infections that:

  1. are unlikely to clear up without antibiotics
  2. could take too endless to clear without treatment
  3. could infect others
  4. carry a risk of more serious complications

People at a high risk of infection may also be given antibiotics as a precaution, known as antibiotic prophylaxis.

Read more about when antibiotics are used and why they are not routinely used to treat infections.


Side effects of antibiotics

As with any medicine, antibiotics can cause side effects.

Most antibiotics do not cause problems if they’re used properly and serious side effects are rare.

The common side effects include:

  1. being ill
  2. bloating and indigestion
  3. feeling ill
  4. diarrhoea

Some people may own an allergic reaction to antibiotics, especially penicillin and a type called cephalosporins.

What happens if you eat moldy bread and own a penicillin allergy

In extremely rare cases, this can lead to a serious allergic reaction (anaphylaxis), which is a medical emergency.

Read more about the side effects of antibiotics.


Mold Allergies and Food Allergies

It is possible, however, to own related food allergies if you own a mold allergy. Penicillium can be found in certain aged and blue-veined cheeses, such as Roquefort and Camembert.

What happens if you eat moldy bread and own a penicillin allergy

There own been reports of food allergy reactions in Penicillium-allergic people who eat these cheeses and other foods with this mold.

If you own an allergic reaction to mushrooms, it's more likely that it's from the mushrooms themselves, but symptoms of oral allergy syndrome own been reported in people with mold allergies who own eaten raw mushrooms. Yeast is another potential food allergen if you own a mold allergy.

You may be wondering how a mold allergy can be related to a mushroom or yeast allergy. The answer is explained by a phenomenon called cross-reactivity.


The Basics of Cross-Reactivity

Cross-reactivity means that there are similar proteins shared between certain foods and certain molds.

What happens if you eat moldy bread and own a penicillin allergy

So if you're allergic to molds, you may extremely well react to foods love mushrooms that contain a similar protein.

There is also ample scientific evidence suggesting cross-reactivity between diverse pollens and raw fruits and vegetables. Likewise, an allergy to latex can predispose people to certain food allergies (mostly fruits and nuts). Doctors own even named this condition "the latex-food syndrome."

The Bottom Line

The large picture here is that while a mold allergy may lead to a food allergy such as yeast or mushrooms, it doesn't mean you'll develop allergies to medications love penicillin.

That being said, a history of allergies puts you at a higher risk of developing other allergies, so it is possible for you to own both an allergy to certain molds and a penicillin allergy, but the two are not interconnected — it's simply a coincidence.

Modern-day penicillin antibiotics are produced synthetically and are not contaminated with mold particles.

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What happens if you eat moldy bread and own a penicillin allergy

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Antibiotics are used to treat or prevent some types of bacterial infection. They work by killing bacteria or preventing them from spreading. But they do not work for everything.

Many mild bacterial infections get better on their own without using antibiotics.

Antibiotics do not work for viral infections such as colds and flu, and most coughs and sore throats.

Antibiotics are no longer routinely used to treat:

  1. chest infections

  2. ear infections in children

  3. sore throats

When it comes to antibiotics, take your doctor’s advice on whether you need them or not.

What happens if you eat moldy bread and own a penicillin allergy

Antibiotic resistance is a large problem – taking antibiotics when you do not need them can mean they will not work for you in the future.


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