Are Vaccines Safe While Using Weight Loss Injections? Treated

Are vaccines safe while using weight loss injections?

Routine vaccines help keep you healthy, active, and avoid the need for medical care. For your health and well-being, it’s important to stay on top of your vaccines, whether you’re taking weight loss injections (WLIs) or not.

Medically reviewed by

Craig Marsh, Clinical Reviewer

Vaccine	Who it’s especially important for
COVID-19	Everyone 6 months and older; especially those 65+ or at high risk for severe illness.
Flu	Everyone 6 months and older; especially pregnant women, people with chronic conditions (like diabetes), and those with a BMI over 40.
Shingles	Adults 50 years and older (2-dose series).
Pneumococcal (protects against pneumonia, meningitis, and sepsis)	Adults 65 and older; adults 19–64 with certain underlying medical conditions or risk factors.
Respiratory Syncytial Virus (RSV) (helps prevent serious lower respiratory infections like pneumonia and bronchiolitis)	Adults 60–74 who are at increased risk; everyone 75 and older.
HPV (helps protect against a range of cancers and genital warts)	Typically recommended up to age 26; adults 27–45 should discuss with their doctor.

Vaccine

Who it’s especially important for

COVID-19

Everyone 6 months and older; especially those 65+ or at high risk for severe illness.

Flu

Everyone 6 months and older; especially pregnant women, people with chronic conditions (like diabetes), and those with a BMI over 40.

Shingles

Adults 50 years and older (2-dose series).

Pneumococcal (protects against pneumonia, meningitis, and sepsis)

Adults 65 and older; adults 19–64 with certain underlying medical conditions or risk factors.

Respiratory Syncytial Virus (RSV) (helps prevent serious lower respiratory infections like pneumonia and bronchiolitis)

Adults 60–74 who are at increased risk; everyone 75 and older.

HPV (helps protect against a range of cancers and genital warts)

Typically recommended up to age 26; adults 27–45 should discuss with their doctor.

Nausea

For example, some people who have a vaccine may experience nausea (or, more generally, gastrointestinal discomfort), which is also a potential side effect of WLIs, particularly when starting treatment or increasing your dose.

So if both the weight loss treatments and the vaccine are affecting you at once, the combined effect could feel stronger.

To make things easier on your body, try to book your vaccine on a day when you’re not taking your weight-loss injection or increasing your dose—ideally, leaving a few days in between.

Headache

Headaches are another common reaction to vaccines.

WLIs can also sometimes cause mild side effects, such as headache or changes in energy and appetite, as your body adjusts to the treatment. So if you get vaccinated while on a WLI, these might overlap, making you feel worse than if you only had one of the two.

So again, it’s important to leave some space between your weekly dose and your vaccination if possible, and drink plenty of water.

Arm pain

One of the most common vaccine side effects is soreness, swelling, or tenderness at the injection site, which is usually your upper arm. These could impact your ability to exercise.

Again, it might be helpful to plan your vaccination on a day where you aren’t planning to exercise intensely (in particular with arm-intensive workouts) the following day.

You can also try low-impact activities that don’t stress your arm while it recovers, like walking, light leg or core workouts, stretching, or low‑intensity cardio.

Blood sugar

Fever can be a short-lived side effect of vaccination, and it can temporarily affect metabolism and cause your blood sugar to spike, especially if you have type 2 diabetes.

If you have diabetes or insulin resistance, this means your blood sugar can fluctuate a bit after vaccination. And if you’re also using WLIs, which can also have significant effects on your metabolism and appetite, this may put extra stress on your body.

So it’s important to monitor your blood sugar after a vaccination if you have diabetes, and consult a doctor if you’re using WLIs and develop symptoms of low blood sugar, such as dizziness, shakiness, sweating, hunger, or faintness.