We've written a number of articles about Shingrix, the recommended vaccine for the prevention of shingles (i.e. herpes zoster), including one going over all of the documented side effects:
The side effects you are experiencing (e.g. muscle aches, a red rash, and itching), are fairly common.
The rash and itching specifically would be classified as an 'injection-site' reaction, which simply refers to side effects occurring locally, at the site where you received the shot (most likely the deltoid region of your arm).
The prescribing information for Shingrix lists the following incidence rates (i.e. how often they occur as a percentage of total people receiving the vaccine) for muscle aches and injection-site reactions:
- Injection site pain
- Age 50-59: 88.4% (i.e. 88.4% of those receiving Shingrix experienced injection site pain)
- Age 60-69: 82.8%
- Age over 70: 69.2%
- Injection site swelling (which may or may not be accompanied by itching)
- Age 50-59: 30.5%
- Age 60-69: 26.5%
- Age over 70: 23%
- Muscle pain
- Age 50-59: 56.9%
- Age 60-69: 49%
- Age over 70: 35.1%
You can clearly see you aren't alone in what you are experiencing.
It should be noted that some individuals experience the side effects of Shingrix more severely than others.
In fact, clinical trials for the drug 'graded' the side effects experienced based on their severity:
- Grade 0: Absent
- Grade 1: Easily tolerated
- Grade 2: Interferes with normal activity
- Grade 3: Prevents normal activity
Looking at injection-site reactions for those aged 50-59, 30.5% of individuals receiving the vaccine experienced them. However, 9% are these injection site reactions were classified as 'grade 3'.
Overall, studies show that the side effects of Shingrix last around 2 to 3 days, regardless of how severe they are. In the next section, I discuss this in greater detail.
Duration Of Side Effects
The prescribing information for Shingrix states, based on the clinical trials for the vaccine, the median duration of side effects experienced is only 2 to 3 days:
The majority of solicited local adverse reactions and general adverse events seen with SHINGRIX had a median duration of 2 to 3 days.
It is important to point out, that regardless of the severity of the side effects you experienced from Shingrix (even if you had a 'grade 3' reaction), the average duration is still around 2 to 3 days.
One of the largest studies completed that evaluated the safety of efficacy of Shingrix was published in the New England Journal of Medicine and states this regarding the duration of side effects:
The reactions were transient, with median durations of 2 to 3 days for injection-site reactions, 1 to 2 days for systemic reactions, and 1 to 2 days for grade 3 reactions.
The same study published a detailed survey of side effect duration, which I have adapted into the below chart:
Shingrix Side Effect Duration Chart
|Shingrix Adverse Reaction||Median Duration|
|Local Pain||2 Days|
|Grade 3 Pain||1.5 Days|
|Local Redness||3 Days|
|Local Redness Grade 3||2 Days|
|Local Swelling||3 Days|
|Local Swelling Grade 3||1 Day|
|Myalgia (Muscle Pain)||2 Days|
|Myalgia Grade 3||2 Days|
|Fatigue Grade 3||1 Day|
|Headache Grade 3||1 Day|
|Shivering Grade 3||1 Day|
|Fever Grade 3||N/A|
|Gastrointestinal Grade 3||1 Day|
*Adapted from Table S3. N Engl J Med. 2016 Sep 15;375(11):1019-3
There doesn't appear to be much of a difference between the rate of side effects between the first and second dose of Shingrix, and just because you experienced a side effect from the first dose, doesn't necessarily mean you will have one to the second dose.
The 'Ask The Experts' section of the Immunization Action Coalition (Immunize.org) discusses this:
Reactions to the first dose do not strongly predict reactions to the second dose. RZV [Shingrix] recipients should be encouraged to complete the series even if they experienced a grade 3 reaction to the first dose.
As a final note on this subject, remember that the duration of time that side effects last, as stated in studies and the prescribing information for Shingrix, is the median number of days. The median is simply the value at the midpoint of the frequency distribution. It doesn't necessarily constitute the average.
Therefore, you could expect side effects to last slightly longer or (hopefully in your case!) shorter than 2 to 3 days.
Nevertheless, it would be unusual for them to continue much past one week (7 days) . If you continue to experience side effects for a significant length of time, or they are hampering your ability to normally function, it is important to see your doctor to be properly evaluated.
SummaryThe median duration of time that the side effects for the Shingrix vaccine last is 2 to 3 days. They could potentially last a few days shorter or longer, but it would be unlikely they continue for over 7 days. Most data suggest that side effect frequency and duration don't differ between the first and second dose.