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Over the course of my allergy shots (immunotherapy), I’ve experience 5 side effects. If you’re considering allergy shots it’s important to know the possible side effects.
Your reactions will likely be different than mine, but I hope my experience provides valuable insight! After all, the last thing you want is to begin receiving allergy shots and experience reactions or side effect that were unexpected.
Choosing to go through with allergy shots is a long-term health decision that can result in significant improvements to your quality of life. They do, however, require patience and a significant amount of time.
If you’re really struggling with your allergies – more than just a few weeks of the year – allergy shots can bring relief.
Below, I’ll share my experience with side effects from the beginning until now (9 years later) and I’ll share my thoughts on whether allergy shots are effective. I hope you find relief just as I have.
My Experience With Allergy Shots
In my early 30’s I was struggling with my health. My allergies didn’t just appear out of nowhere, rather, my allergies had slowly crept up on me and began to affect my every-day-life.
I was in graduate school, busy with studying and an internship. At first I ignored the allergy symptoms because I had always experienced them.
As my health was snowballing downward (not an exaggeration) I stopped going to my internship. I continued to study but slept 12 hours a day. In class I would struggle to keep my eyes open.
I had no idea what was happening. Was this normal?
Eventually, I wound up at an allergist. He asked me a few questions and chose to tested for a few allergens. I tested positive for most things and began allergy drops. After a year I didn’t find much relief.
At this point I knew allergies were causing me to feel ill, so I made an appointment with another allergist. This time I was tested for over 100 things (environmental not food).
Again, most of my results came back positive.
I’ve been working with my allergist for 9 years and I’ve learned how allergy shots work (read my personal review of allergy shots here). I’ve experienced a few side effects and I’ll share them with you below.
Types of Allergy Shots
It’s important to note that allergy shots are currently used for environmental allergens, not for food. You can be tested for environmental and food allergies, but the best way to manage food allergies is avoidance.
Environmental allergens (or aeroallergens) are outlined below:
- Pollens (grasses, weeds, trees)
- Dust Mites
- Stings (bees etc.)
The test is relatively quick and only takes less than 30 minutes. It’s also painless, with no injections (you can read more about my testing process here). Once you’ve been tested and examined you doctor will outline the options available.
Standard Allergy Immunotherapy
Most of my time with allergy immunotherapy has been the “standard” process. There are 2 parts to standard allergy immunotherapy.
Build up phase
The build-up phase is a slow process of weekly or twice weekly shots. The shots are given in the back of the arm or the thigh.
The first shot will be extremely weak, and if you don’t experience a major reaction to the shot the next dose will increase slightly. The shots contain the actual things you’re allergic to, so it’s important to go slow and minimize a bad reaction.
It took me 1 year to build up to a strong dose. You might be thinking “that’s too long”, but if your allergies were as bad as mine it’s worth the wait. Slow and steady your health will likely improve.
The second phase of the allergy shots is the maintenance phase. As the name suggests, you will maintain the strength of shot for a long period of time.
One of the good things about the maintenance phase is the shots are spread out further, sometimes weekly, biweekly, or even monthly depending on your improvement.
During the maintenance phase your doctor might retest you to find stubborn allergens and then readjust the dose. My dose has recently been readjusted so I am taking my shots closer together for added improvement.
As the name suggests, rush immunotherapy is meant to speed up the shot process. Not all allergists offer “rush immunotherapy” but if they do I recommend you consider it.
One of the main reasons people don’t experience relief with allergy shots is because they miss shots or can’t commit to the schedule.
Rush immunotherapy consists of multiple shots spread out over a single day (or few days). The aim for rush immunotherapy is to reach maintenance dose quickly, where the majority of benefits begin to occur.
Rush immunotherapy works great for people who:
- Want faster relief
- Are willing to experience multiple shots quickly (tough guys and gals)
- Have a busy schedule and can’t receive shots every week for a year
- Are only mildly allergic to a few things
Rush immunotherapy has a higher risk of reactions.
Cluster immunotherapy is a hybrid of rush and standard allergy shots. During your shot schedule, you might receive 2-3 shots each visit to speed up the process.
Remember the goal is reaching maintenance dose and once you reach it you’ll likely feel more relief.
Cluster immunotherapy also has a higher risk of reactions.
Allergy Shots Side Effects for Adults
Allergy shot side effects or reactions are usually minimal and easy to manage. Because you’re being injected with allergens sometimes your body can overreact.
For this reason it’s important to always carry an Epi-Pen with you to the doctor, in your car, to work/school. I’ll explain the side effects and reactions I’ve experienced during my 5 years of allergy shots.
Immediately after my shot I’ll usually have a small bump (smaller than marble). The bump isn’t painful or irritated, rather it’s a bump because of the fluid.
10-60 minutes after the shot the bump goes away. This didn’t happen every time I received a shot but I learned that it wasn’t a serious issue.
An hour or so after the shot I usually experience light redness around the shot location (size of silver dollar).
When I first began shots I didn’t have skin reactions. Only when I became closer to my maintenance dose did I begin to see redness. I actually appreciate seeing the redness because I know my body is still reacting and there might be room for improvement.
The redness isn’t painful, just something I can see. It remains the day after the shot but dissipates the 2nd day.
Occasionally, the shot location will itch a few hours after receiving the shot. This usually goes away within a day.
Sometimes I wake up after sleeping to find scratch marks on my leg. I have eczema so some of my allergies make my scratching worse.
Worsening of allergy symptoms for 2 days after shot (more the 2nd day)
After my shots I almost always experience a slight worsening in allergy symptoms for 2 days after the shot.
In my opinion this should be expected, right? You’re being injected with allergens and your body is reacting. For 2 days after the shot I usually take an extra anti-histamine.
My eczema always gets a little red (different parts of my body) and improves a few days after shots.
Fatigue for 2 days after shot
Fatigue was one of my main allergy symptoms so it’s not a surprise that I’m easily worn out after a shot. I think my immune system goes into overdrive when I receive the shot and makes me tired.
The fatigue is manageable but I’ve learned to not schedule my shot around important work events, presentations, or meetings.
I asked my allergists about this side effect and they didn’t say it was common, however, it’s important to understand that people experience different allergy symptoms and reactions to allergy shots.
Once I reached maintenance dose, my fatigue became less problematic. Needless to say, I have much more energy now!
Reactions To Allergy Shots Pictures (My Pictures)
I’ve included a few of my photos after allergy shots. The first allergy shot picture is the same day and is about 5 hours after the shot.
I believe this is normal and nothing to worry about. Conversely, if there was no reaction at all I’d think the shot was too weak.
The second photo (below) is the 2nd day after getting my shot. Notice the redness has significantly decreased. By the 3rd day there is no mark.
Can Allergy Shots Make You Sick
Everyone tolerates allergy shots differently. In fact, some people might not tolerate them at all.
I’ve never been sick from allergy shots, but I have noticed that if I have a cold or the flu and I get an allergy shot my cold or flu will worsen significantly.
I’m not a doctor so I would never answer this question definitively but think about the situation. With allergy shots you are being injected with things your body regards as harmful.
Frequent shots eventually teach your immune system to settle down and stop reacting so strongly.
The tips that I’ve used with my allergist:
- Reschedule if you’re under stress at work
- Reschedule if you’re ill from a cold or flu
- Understand that the shots will exhaust your immune system for a day or two after the shot (however I’ve also been told I should feel relief immediately after a shot?)
- Communicate to your allergist if you feel the shots are too strong (I had to do this and when we reduced the shot amount I felt much better)
- Communicate to your allergist your reactions
- Keep a journal – it’s useful to look back on and understand if a reaction is normal or out of the ordinary.
Allergy Shots Effectiveness – My Opinion
Are allergy shots effective? A few years ago, prior to starting allergy shots, I was in a horrible place.
I couldn’t make it to work, I stopped socializing, and I stopped exercising. I became obsessive about controlling my environment and reducing any stress.
I didn’t know what was causing me to feel bad and I didn’t know what to do.
Thankfully I was allergy tested.
But that didn’t solve the problem. The first allergist I visited didn’t help me.
He tested me for a couple things and gave me allergy drops – there was very little communication or explanation on his part. After that experience, if you were to ask if allergy immunotherapy is effective I would have said “no”.
Thankfully I was retested for allergies by a reputable allergist.
I received the full spectrum of tests and the process was explained to me. We decided on a way to move forward. I strongly believe that allergy shots are effective.
Over the past few years I’ve reduced my allergy symptoms by about 80%. I can breathe through my nose (something I could never do before) and my eyes are less itchy.
My fatigue is gone. I only need 7 hours of sleep a night and I wake up energized and ready to go. I’ve also been able to hold a job.
I suffered from allergies year-round, not just seasonally. I was desperate to find a solution and I’ve followed the schedule outlined by my doctor.
I’ve also been retested a few times to make sure the allergy shots are working. Guess what? I no longer react to many of the allergens I first reacted to.
If you’re tired of suffering, consider SCIT immunotherapy. Allergy shots are effective and they can help you, but take time to find a reputable allergist and commit to the schedule.
Allergy shots aren’t fun, but they work.
In this article we discussed the side effects of allergy shots in adults. I shared my experience as an adult with allergies including the challenges and success using allergy immunotherapy.
It’s important to note that allergy shots aren’t given for foods, rather they are for environmental allergens, also called aeroallergens.
Environmental allergens are made up of pollen from grass, weeds, and trees, dust mites (indoor), mold, pet/animals, and yeasts. Allergy shots are also used for insect stings like bees.
I experienced year-round symptoms from environmental allergies and I’m allergic to almost 100 things.
The shots have helped me reduce symptoms of fatigue, eczema, rhinitis, conjunctivitis, and irritability but because the shots contain the same things I’m allergic to, they do have some side effects, or more appropriately “reactions”.
The side effects or reactions I’ve experienced are a small bump at the injection site, redness, itchiness, slight worsening of allergy symptoms (eczema), and fatigue. After 2 days I usually bounce back and feel energized.
If you’re considering allergy shots, think about the time commitment. Can you commit to multiple years? If your allergy symptoms are as bad as mine, the answer will be clear.
Also consider the types of allergy shots: standard, rush, or cluster. There are various benefits of each option.
I’ve been on allergy shots for 6 years with tremendous benefits (80%) and very little side effects. I’ve been retested a few times during my shots to see my progress and my allergy shot dose has been adjusted (I believe this is very important).
Because the substance in the shots isn’t synthetic, there won’t be chemical side effects that you need to worry about.
If this sounds like an option for you I encourage you to search for a reputable allergist and be tested for allergies. Once you determine what is bothering you, your doctor can recommend solutions to improve your health.