What are the side effects of the Johnson & Johnson vaccine?

side effects Johnson & Johnson vaccine, blood clot
© Stanislav Sukhin

Here, we discuss some of the common misconceptions about side effects of the Johnson & Johnson COVID vaccine

The Johnson & Johnson vaccine can create an efficacy of 66% in one dose, while mRNA vaccines like Pfizer need two doses to create strong enough protection. The vaccine can be kept at a standard fridge temperature for three months, then at -20°C for two years. This means that an existing cold supply chain can transport the vaccines.

The Johnson & Johnson vaccine is different to all others, as it only needs one dose to protect against COVID hospitalisation and death. It currently has Emergency Use Approval in the US.

A new note, added 12 July by the FDA, connects the vaccine to Guillain-Barré syndrome. Currently, it is 0.0008% likely that you will have this reaction, making this an extremely rare side effect.

However, the latest fears about blood clot risks may have damaged the perception of how safe this vaccine is. Here, we look at the science behind any existing side effects for the Johnson & Johnson vaccine.

1. What are the common side effects for Johnson & Johnson?

The general impact on the arm and body are the same as with other vaccines. With UK vaccination data on Pfizer and AstraZeneca, it seems that one fourth of people are getting side effects. Within that group, scientists found that if a person had previously had COVID-19, they would likely have stronger side effects. 

Usually, a fever or headache means that the immune system is accepting the new defences against the virus. The side effects of the Johnson & Johnson vaccine are a good sign.

In the arm:

  • Pain
  • Redness
  • Swelling/itching

In the body:

  • Fever
  • Chills
  • Rash
  • Nausea/vomiting
  • Headache/dizziness
  • Arthralgia
  • General itching
  • And fatigue

2. Will the Johnson & Johnson vaccine give me blood clots?

It is highly unlikely, but possible. 

There are currently 17 cases of blood clot out of 8 million doses given.

That’s a 0.002125% chance of experiencing a major blood clot, after taking the one-dose vaccine.

Though the US temporarily suspended use, the vaccine is back with a warning attached. However, Denmark decided to permanently suspend the vaccine.

It is more likely that birth control creates a life-threatening blood clot.

The side effects are happening in women between 18-48 years old, with symptoms coming six to 13 days after their vaccination. Those with low levels of platelets are more likely to be at risk.

The FDA ask that: “People who have received the J&J vaccine who develop severe headache, abdominal pain, leg pain, or shortness of breath within three weeks after vaccination should contact their health care provider.”

The full list of blood clot symptoms are:

  • shortness of breath
  • chest pain
  • leg swelling
  • persistent abdominal pain
  • neurological symptoms (including severe or persistent headaches or blurred vision)
  • easy bruising
  • tiny blood spots under the skin beyond the site of injection of the vaccine

3. Can Johnson & Johnson side effects make me infertile?


The Johnson & Johnson vaccine is not an mRNA vaccine, like Pfizer or Moderna. Both Pfizer and Moderna faced the suspicion that awaits a new type of vaccine – with people wondering if their DNA would be permanently changed, or if they would be able to create children after the vaccine.

In December, 2020, a German doctor and anti-vaccine supporter, begun to create a false link between syncytin-1 (an ingredient in the vaccine) and the human placenta. His argument was that they share genetic makeups, meaning that the vaccine could then attack the human placenta and make the body unable to carry a baby.

But this is impossible. The antibodies created after the vaccine are specifically coded to fight the virus and protect the human body. If the antibodies were to suddenly turn on the human body, this would have been spotted at Phase One, Phase Two and especially the huge Phase Three stage of clinical trials for every single COVID-19 vaccine.

When it comes to Johnson & Johnson, the ENSEMBLE study had participants that later went on to become safely pregnant.

So far, more than 30,000 pregnant women have taken the Pfizer and AstraZeneca vaccines. They reported no adverse side effects to the Center for Disease Control. Real-world Johnson & Johnson data is going to become available to the CDC soon.

4. Can I have an allergic reaction to the vaccine?


A severe allergic reaction would usually occur within a few minutes to one hour after
getting a dose of the Johnson & Johnson vaccine.

What are the symptoms of a severe allergic reaction?

  • Difficulty breathing;
  • Swelling of your face and throat;
  • A fast heartbeat;
  • A bad rash all over your body;
  • And dizziness and weakness.

Check if you have any problems with these ingredients:

  • Recombinant;
  • Replication-incompetent adenovirus type 26 expressing the SARS-CoV-2 spike protein;
  • Citric acid monohydrate;
  • Trisodium citrate dihydrate;
  • Ethanol;
  • 2-hydroxypropyl-β-cyclodextrin (HBCD);
  • And polysorbate-80, sodium chloride.

If you are not sure about a reaction you are having, please contact a healthcare professional. 


  1. Well I got the J&j vaccine on April 2 and on April 23rd I was diagnosed with blood clot in my leg. How many other people got blood clots that weren’t the cerebral kind which are the only ones being talked about. I’m sure there are others then just me.

  2. I got vaccine 4 days ago and have gastro problems.. Throwing up constipation, now diarrhea and passing some blood. Called Dr 8am. and got return call at 3:40… They suggested I go to ER.. Somewhat confused if it is emergency why wait 8 hours to notify me. Weather is terrible here got sick dog and now this.

  3. I received the J&J vaccine on April 9th, less than 2 hours later I was having severe pain in my hips and the back of my thighs. It is now May 22 and I still have the pain. I have been to the Doctors and they have me on nerve pain medication. So far there is no improvement. The only way I make it thur the day is to over dose on Advil.

    • Barbara, I am having the same pain in my hips and back. Most of my joints hurt, difficult to sleep with the hip pain, it is hard for me to walk without a limp. This started about 3 weeks after the J&J vacine shot and has lasted for several months now. I am 68 years old and have always been health conscious, prior to this I felt like I was in my 40s. Now I feel like I’m in my 80s. I have gone to my doctor, had a blood test, everything looked fine to him.

    • Hi John, I am having the exact same issues. Extreme headaches and even went to ER from “searching for words I already knew”. Just looking for clarity and wondering if anyone else is having these symptoms. How long after the vaccine did this start happening for you? Have you found a solution for the headaches or know what’s going on?


  4. Where is a site to get real data? Just telling me no it won’t cause infertility doesn’t work for me it’s a new vaccine how is this known, where is the data? It has to be somewhere?

  5. I received J&J on 5/14/21. 2 hours later I started having SOB.The next day it got worse and I had to call 911 because I couldn’t breath. In ER I was diagnosed with pneumonia and was in the hospital for 7 days on oxygen because it would not stay above 87%. Today 6/4/21 I am still on 3% 24/7, dizzy, lightheaded also and can’t was for more that 10 feet.

  6. I had the Jenssen vaccin 14 days ago (June 2021) at the local Phamacie in France Eymoutiers. Obviously they are not as well practiced as a nurse. I felt a mild sensation but it had come straight from the fridge ! Side effects so far about the same as the annual flu vaccine which I also have in Septembre that is so say very mild to nothing. Have developed a slight stiffness in the arm, my left arm. This aches a lot at night so I take Ibrufen 400. Vaguly tired, a bit irritable but otherwise ok. Its very hot here at the moment 35*.

  7. One and done on June 11th, 2021. Did have pain in the right hip a few days later. My Covid long symptoms improved, not having problems breathing or catching my breath anymore.

  8. My friend currently sits in a hsptl. In Texas. Her future isn’t clear. She’s had severe brain damage, part of her skull had to be removed and she’s losing at minimum, 1 finger, possibly 2. All due to j&j vax, which led her to have blood clots, in brain and other areas, low platelets, adrenal glands hemorrhaging, brain swelling. She’s been in an induced coma for weeks. Now that they’ve brought her out of coma she remains unresponsive. Her eyes and limbs sometimes moving but believed to be involuntarily.
    Neurologist can’t say for sure just yet as to the extent of damage her brain has suffered.

  9. Received J & J vaccine on 06/10/21. 4-5 hours after receiving vaccine experienced fatigue, headache and over all flu-like body ache. Day 2: Slight fever and lesser body ache. Day 3 PM: broke out in hives so bad I thought I had poison ivy. Neck, chest, stomach, back, arms, hands, legs and feet all covered in itchy hives. COuld not sleep and felt like my skin was on fire. Day 4,: Hives subsided in AM only to return in PM. This continued for four three more days, hives at night. For the following 2-3 days, hives would only return when I would go outside in the heat or when sweating. Would I get the J & J vaccine again? No. I have never had hives in my life before this vaccine, and something seems horrible wrong with the way it caused this kind of delayed skin reaction. If a booster or additional shot is necessary, I will wait until the FDA approves Covaxin.

  10. I am a 62-year-old woman and my name is Ana. I had no side effects after taking the shot in April 2021. I had natural immunity after having the Covid in January 2021 with very mild symptoms. The reason I went for the vaccine was that I had the long haulers and was having major anxiety, couldn’t sleep, had heart palpitations, trouble;e breathing so I went and got the shot. I did start feeling better.
    A few months later I have had skin that feels like ants are crawling all over me, fatigue and I can sleep 12 hours and feel totally unmotivated to do anything. I have always been a bit OCD and have had to have my house perfect but not anymore. I’m not sure what is going on but if anyone else is experiencing any of these symptoms please contact me.

    • I am 24 y/o, got the J&J vaccine one month ago… I´m also experiencing constant fatigue, sleepiness and no motivation, even if I sleep for a long time. I though it could be something else but after really thinking about it and checking up on myself, I believe it could be a long-term side effect of the vaccine.

  11. My grandson requested he get vaccinated so he got the JJ shot Less than 5hrs later he developed fever nausea chills with racing heart and high BP ( 163/103 and his hr was107 he also passed out twice I want to let people know about this He just had his 23rd BD. He still has problems Note he got the shot last week of April . I had to bring him to Er 3 times!!! Where they tried to tell him he has Anxiety!!

  12. Received shot yesterday on 7/28/21 – arm a little sore – no side effects. Taking a low dose of bayer asprin just in case of blood clots.

  13. Afternoon, I got j&j on the 7th of May 2021, since then was not well it started with headache, dizziness, coughing, on the 1st of June I tested for covid19 because I was not getting better but I tested negative. I continued being sick symptoms adding difficult breathing, no smell no taste, sore throat, I tested positive for covid19 on the 7th of July 2021, the biggest problem now my hand where I got vaccinated it’s vibrating & become numb, once or twice a day. Yesterday on the 1st of August 2021 my Son was having a magnet I said let Me see this trick people are saying about magnet sticking where there’s vaccine, surprisingly the magnet stick. My only trust now is God because I don’t know what is happening really

  14. I have developed itchy, red, inflamed eyes within 48 hours of receiving the J&J vaccine. The skin around the eyes feels burned and sore like a bad sunburn. My eye’s white areas turn pinkish and clear up a little then turn pinkish again. The corners of each eye burn, sting and itch constantly. There is a gooey, slimy discharge and tears constantly coming from both eyes and mornings have been finding my eyes sealed shut with discharge. I get blurred vision as if the natural lubricant of my eyes has gotten thickened and lobbed up at times in my field of vision. My eyelids go from normal to puffy and swollen. `there are irregular pink patches of skin around and under the eye and eyelid that burn feel tender like a sunburn as well. Allergy eye drops and regular eyedrops provide some temporary minor relief. Ibuprofen and tylenol and Alive do not seem to have any effect. i am now on day 3 of these side-effects. I have never had anything like this before and must assume it is somehow linked to the vaccine. Contacting my doctor today for help. I know this is better than gasping for air on a respirator but jeeez, this ain’t exactly a cake walk when your vision is affected, you look like a wino that someone threw hot grease into their eyes.

    • Hi Donald,

      Got my vaccin 2 days ago. 3rd day my eyes were itchy all day, then at night, the left one turn red. I guessed it was a symptome.
      But tell me are you still having it?


    • Dave here from NY. I have the same eye problem. 1 week after the jj shot. Its been over a month now. 3 days ago I went to the local urgent care and got drops for conjunctivitis. Day 3 of the drops and not much relief.

  15. I would like to know if anyone is having high blood pressure, my mom got the J&J vaccine a couple of months ago and is now having high blood pressure. My mom has never had high blood pressure and it does not run in our family. She is now on high blood pressure medications.

    • My wife got the J&J vaccine 2 months ago and she never had high blood pressure issues. I know because she always bragged at me since I do. Now her blood pressure seems to be all over the place. One minute she is above 140/90, next minute down to 110/70. This is daily and she is not doing anything different.

  16. i am 26 after j&j vaccine first night was like crazy couldn’t sleep my body was shivering with pain now after a week headache and body pain is my Best friend . i wish i didn’t get that vaccine . never had any fever and symptoms before vaccine now i feel weak .

  17. J and J Vaccine on Aug. 9, 2021….No problems AT ALL UNTIL DAY 4,5,6….Flu-like Symptoms (and I have only had the Flu once in my entire life) Days 7 and 8 were not as bad but suddenly, on day 9, my neck and the left side of my face is NUMB…the numbness is extended to the “gums of my teeth”, also on the left side. Slightly feel dizzy with a tingling sensation around my mouth as the morning progresses. I am normally in excellent health, never “get sick” so this feeling of “un-well” is foreign to me. Praying for everyone…with or without the vaccine….

  18. Hi, I’m Gloria….I got my J&J March 4,2021. No side effects. I’m June I started having breathing problems. They are getting worse. I can’t do normal things as before. I’m 73 years old. I already have bad lungs nothing like now. Does anyone else have the same effects months later?

  19. If you are reading this, stand firm do not compromise your body.DON”T DO IT!!!!
    I am 62 Years old woman, healthy, take vitamins, eat clean, work out…PS I was forced, pressured by my job.
    I have been sick for 4 days, I had covid, I had 583 count antibodies, it was against my judgment.
    My body is aching all over, cills, tired but no sleep in 3 days, no appetite, headaches my arm is stiff joints, lions, the body feels weird.
    It is not FDA-approved, it is your body! too many side effects!!I wish I read the reviews before getting any shot!

  20. I had the J&J vaccine on 3/6/21. Several weeks later I had shocking lab results, indicative of renal failure. I have not seen any other reports of this and would like to know if others experienced this. Thanks, Linda, in NM,

  21. Im Sandile Fakudze vaccinated three weeks back. I feel dizzy and tired everyday. Please help, always feel like sleeping.

  22. appx 2 weeks after J&J on 3/31/20, I began feeling an odd feeling in my thigh/hip/buttocks, mild but a bit strange, and it continued to intensify bit by bit, so here I am 8/23/21 having been somewhat incapacitated for several weeks off and on. a month ago I began a landscape project that pushed me over the edge, somehow my lower back pain from work merged? into my hip, and so I limp on a good day, otherwise the pain can reach levels similar to having a kidney stone, bringing me to my knees, I know!…Do I blame J&J or the physical work that was doing??? perplexed ! am now reading about gullian-barre’ syndrome, go figure

  23. Had my J&J Jab on the 28th of August its my 3 day since and i felt okay yesterday morning then became extremely tired, today i felt also okay and again very weak, my stomach and chest is burning feels like i drank steaming hot water as it is burning, eyes are red and burns alot hopefully it will subside with time

  24. I wish i had gone through this reviews before letting my pregnant wife take j&j vaccine shots yesterday. She’s been having severe abdominal pains for the past 9 hrs. I pray nothing bad happens to her.

  25. Well I am convinced now not to take this vaccine!!! Getting the virus probably is a
    bigger risk for my wife and I but we are currently healthy so we aren’t going to risk it!!! We already had the virus I am sure if that!!! Good Luck and thanks for your comments!!!

  26. I had my vaccine early March about 3 weeks later my Dimer test came back elevated for blood clot had leg bruising swollen nothing found on ultrasound. Beginning of April now I have been diagnosed with Hyperthyroid. Sounds crazy but where I had the injection my arm tends to get hot..

  27. did any one have tingling sensations and bones pain that comes and goes but is still there weeks after the shot and is sometimes stronger espacialy in fingers and toes hands and anckles ?

  28. I had j j 8/27. Just sore arm at first. 9/5 I started intestinal pain. It has gotten pretty severe and cant button my pants because of the pain. I do have a preexisting FAP and have no colon with a j pouch. The swelling and intense pain is still here on 9/9. Not sure I should have gotten any shot with the FAP. My daughter had the phizer and actually had different symptons at first and had the abdominal issues also. She also has the FAP and pouch. She may not get the second shot in fear that the symptoms may be worse. She thinks that it is the protein used in the vaccine that is giving us the problem.

  29. Got the J and J shot AUG 26 Got very bad belly pains and my intestings hurt Won,,t Take any more I am 90 years old Two much for me I hope it will go away soon I need a month to feel better

  30. Got J&J two weeks ago, and have had weird tingling in my hands, feet, face and head on and off ever since. First time it happened I freaked out because I thought maybe I was having a stroke. I also feel nauseous periodically after I eat. Went to the doctor yesterday and she basically just scoffed at me like it couldn’t be the vaccine and implied I just have anxiety.

    • it’s not anxiety ,i had that too now it’s been 29 days and i still have muscle pain that comes in goes in whole body doctors also told me it’s anxiety but it’s not it’s the vaccin and many people are having this problem for mounths and the worst part is that no one seems to answer what did the vaccin harm in our bodies that it’s causing this

  31. My son is 48 had the jaj vaccine after 4weeks still has weekness in arm of vaccine and foggy in head. Is this serious as it is third world country and I’m in Australia thank you Jenny

  32. I had the J and J shot over 3 months ago and continue to have tingling and loss of feeling in feet and hands, along with darkened and bulging veins that started about 3 days after I got the vaccine. I never had any of these issues before and was in great health. The doctors just say I’m getting older. They got that right. I think the vaccine aged me about 10 years on one week. The “free” vaccine has so far cost me about $3000 in useless medical care.


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