PQQ side effects
Across 149 first-hand reports, people mentioned a side effect 8 times (about 5 per 100 reports). The most common: anxiety, renal inflammation, malaise. User reports show what people notice — they can't tell you whether PQQ is safe for you.
Reported side effects
anxiety2
renal inflammation1
malaise1
mental chatter1
stimulation1
headache1
insomnia1
In their own words
“strange as I take Ubiquinol pretty regularly, but PQQ made me feel like shiat.”
“I take 20mg PQQ about 3 times a week. I usually find that it gives me a boost in mental energy, but if I take it every single day I start to get too much chatter going on upstairs.”
Is PQQ safe? What the research covers
BResearch: Moderate0 meta-analyses · 8 randomized trials on PubMed
None of the top reviews we found focus on safety. All research on PQQ.