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olivia_quinn2026-04-18

I was just prescribed Pfizerpen G 20mu Inj, 1vial for a severe bacterial infection. It's an antibiotic that's administered as an injection, either into a vein (IV) or a muscle (IM). The doctor mentioned it can be harsh on the stomach, and the side effects list is daunting. Has anyone else had experience with this medication? Curious about the side effects, especially the urgent ones like allergic reactions and high potassium levels. Also, any tips on managing the potential stomach issues?

1 min read
last active 4/18/2026
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Comments (10)

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peter_moore4/14/2026

My friend had to take this for a serious infection. She kept a journal to track her symptoms and side effects, which helped her communicate effectively with the doctors. It was really helpful. Also, she found out that ginger tea helped a lot with the nausea she experienced.

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logan_johnson4/15/2026

Avoiding any spicy or greasy foods could help make things more manageable while your body is under stress from the infection and the medication. I had to be really strict with myself.

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frances_pierce4/15/2026

Reporting side effects to the FDA is a good idea too. I did it, and it helped me feel more in control of the situation. You can also talk to a pharmacist for more personalized advice. They're a great resource.

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ethan_harris4/15/2026

Feeling extremely tired or weak and having chest pain are the ones you need to watch out for. Don't joke around with that stuff, okay?

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philip_knight4/15/2026

I had to take this for a nasty infection a few years back. The allergic reaction symptoms were no joke, and I had to learn them like the back of my hand because they can be severe. Stay alert and call your doctor if anything feels off. I ended up okay, but it was scary for a while.

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robert_stephens4/15/2026

Yep, unfortunately, diarrhea is common. I didn’t want to make my infection worse by getting one of the super serious forms because I kept ignoring the symptoms. Once I started treating it seriously, it cleared up in a few days.

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frank_vargas4/15/2026

Never had it via muscle injection, but IV was manageable. They gave me an antiemetic to help with the potential stomach upset, and it worked wonders. Also, I kept hydrated and avoided alcohol. The key is to listen to your doctor and follow their instructions closely. You got this!

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linda_fernandez4/15/2026

I’m a bit worried about getting a reaction to the injection. What did you guys do to avoid irritation at the injection site?

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billy_cook4/15/2026

I had muscle pain on top of the infection, but the doctor started me on an NSAID to manage it. I also had my blood checked for potassium levels. Made sure to ask about how the medicine was manufactured — I needed the peace of mind.

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elena_vargas4/15/2026

The side effects are a bit scary, but it's important to remember that everyone's experience is different. Keep an eye on any symptoms and talk to your doctor about any concerns. I took it once and only had mild stomach issues.