Having an allergy to any substance can seem like it’s taking over your life, the symptoms can be severe and debilitating, and you more than likely find yourself constantly checking food packaging labels for the ingredients. Food is one of the main allergens, but food packaging is not the only label you should be checking if you’re trying to avoid an allergic reaction. 

Many people aren’t aware that medicines also have many ingredients in them, some of which are foods that we eat or are intolerant to. Lactose, soya, wheat, and peanut oil are just some which are found in medicines. We’re all guilty of neglecting to check the patient information leaflet but if you have a severe allergy this should be routine when starting any new medicine. One of the most common and serious allergies is peanut allergy, which will be the focus of today’s blog post as many aren’t aware that this substance is used in some common drugs. 

What is a peanut allergy and what are the triggers?

peanut allergy 

It’s commonly believed that if you have an allergy to peanuts then you must be allergic to all types of nuts, but this is not the case. Peanuts belong to a different family of plants to tree nuts such as almonds, walnuts and cashews, in fact, they’re a legume. However, it is possible to also be allergic to tree nuts if you have a peanut allergy. 

The proteins in peanuts can cause a severe allergic reaction with symptoms such as itchy skin or hives, itching or tingling sensation in or around the mouth or throat, nausea, and congestion in the nose. These are some of the mild symptoms but in more serious cases allergy sufferers may experience anaphylaxis if they’re exposed to peanuts. 

Anaphylaxis is a medical emergency as the symptoms can be life-threatening. This type of reaction may cause swelling of the tongue and/or throat which may lead to difficulty breathing, the person may also be wheezing, coughing, and finding it difficult to speak, and in the worst-case scenario they may lose consciousness and collapse. 

Allergic reactions can be unpredictable, each time can vary in severity so it’s best to always be prepared in case you’ve accidentally come into contact with peanuts as highly refined peanut oil can be found in a lot of products.  

Peanut oil that is refined is used more in food and pharmaceutical products because it’s less likely to cause a reaction, however, it’s still possible for an allergy sufferer to have a reaction from refined peanut oil. The proteins in the peanuts are responsible for the allergic reaction, and in refined peanut oil, the majority of the proteins are removed. 

Medicines containing peanuts

It’s just as important to check the label on medicines as it is to check food labels when it comes to allergies. All medicinal products should clearly display on packaging if it contains peanut oil. In some cases, there may be variations in the name unless it clearly states ‘contains peanut oil’ many people are none the wiser if it’s phrased as ‘Arachis oil’ or ‘Arachis hypogaea’ which are alternative names for peanut oil. Some people aren’t aware that if a medicine has ‘refined Arachis oil’ in the ingredients this means peanut oil. This can be quite misleading for many patients so it’s important to get familiar with the different terms for this ingredient.

Although refined oil has been found to be safe for those allergic to peanuts, all food and medicinal labelling should advise not to use the product if they have an allergy to peanuts whether it’s unrefined or refined. 

If you have a food allergy checking food labels and asking the restaurateur if they include your particular intolerance on the menu is all second nature, and this should also be the case when it comes to medicines. Always remember to inform your doctor or pharmacist of your allergy to ensure that any medicines that are recommended or prescribed to you are safe for you to take. Double-check by reading your patient information leaflet for the list of ingredients. 

It’s also important to know that if the list of ingredients doesn’t contain peanut oil but does contain soya you should steer clear of using this product. This is because soya and peanuts come from the same plant family and it’s thought that those who are allergic to peanuts may also be allergic to soy. Soybean oil is used in a lot of food products and some medicines so it’s important to look out for this ingredient when checking your patient information leaflet. 

soybean allergy

Peanut allergy medications to avoid

There are some common or possibly everyday medicines which you may not be aware contain peanut oil. Here are just a few that contain the allergen. 

1. Progesterone capsules

Progesterone is a natural sex hormone that is involved in the menstrual cycle and pregnancy. A synthetic version of the hormone is given to some women in the form of progesterone capsules as part of hormone replacement therapy (HRT) which is used to ease the symptoms of menopause, and may also be used to bring on periods if menstruation has stopped. However, many of these women may also have a peanut allergy and are unaware that progesterone capsules contain soya, peanut oil, or legume derivatives.  

2. Some types of the contraceptive pill

The contraceptive pill is used by millions of women but there are some which contain peanut oil. Desogestrel is a type of mini pill meaning it only contains the progestogen hormone and is used to prevent pregnancy. Desogestrel contains soybean oil and should not be used by those who have a peanut allergy. Other contraceptive pills which contain desogestrel include Cerazette and Cerelle, so if you’re considering taking any of these and you have a peanut allergy, speak to your GP first. 

3. Over the counter ear drops

Ear drops are used to soften the build-up of hard wax in the ears and Cerumol ear drops, in particular, use peanut oil to do so. It’s even more important to check patient information leaflets of the medicines we buy over the counter as there is no doctor approval over whether the medicine is suitable for you, however, you can ask your pharmacist for advice if you’re unsure.    

4. Multivitamin drops

Abidec multivitamin drops are another over the counter medicine which contains peanut oil and is given to babies and children to prevent vitamin deficiencies.  Unless you’ve read the label you may not know that this product contains peanut oil. Peanut allergies usually develop in childhood and are more common in this age group. 

5. Some eczema creams

For many years research has looked into the relationship between eczema and peanut allergy. It’s thought that eczema may be the trigger of or triggered by food allergies including peanuts. It’s also been suggested that the peanut oil in some eczema ointments and creams that are given to infants may cause sensitisation to peanuts. Eczema treatments such as Dermovate may contain some Arachis oil and therefore has a risk of causing an allergic reaction. 


Other products containing peanut oil

Products containing peanut oil

There may be more medicines that possibly contain unrefined or refined peanut oil, and here are just a few to be cautious of if you have a peanut allergy.

  • Siopel barrier cream contains Arachis oil 
  • Calamine oily lotion contains peanut oil
  • Isotretinoin capsules used to treat acne contain soya
  • Sustanon is a testosterone injection that contains Arachis oil

What to do if you’re accidentally exposed to peanuts? 

If you’re aware that you have an allergy to peanuts you’re likely to be scrupulous when it comes to the medicines you take and the food you eat. But if you’ve mistakenly taken medicine without checking the ingredients and you’ve been exposed to peanut oil here’s what to do. 

You shouldn’t have a severe reaction if you’ve been exposed to refined peanut oil, however, this allergy is unpredictable and there is a possibility of severe reaction. If you’re showing symptoms of anaphylaxis you should go to your nearest A&E department to receive emergency treatment. 

If you have a known allergy you should also keep an EpiPen on you at all times. An EpiPen is a device used to treat anaphylaxis by injecting a single dose of adrenaline as soon as the symptoms appear which reduces swelling in the mouth and throat to open the airways and make breathing easier. It also maintains heart function and blood pressure levels. EpiPen should only be used once during a reaction and it is a life-saving device, particularly if you’ve been exposed to peanuts accidentally and a reaction is suddenly brought on. 

It’s important to remember to avoid any medicines that contain peanut oil as although they may be refined, some proteins may still be present. 

Knowledge is power when it comes to living with and managing your peanut allergy, knowing which products contain peanut derivatives and avoiding these can be life-saving.