intraperitoneal

Intragastric and Intraperitoneal Administration of Cry1Ac protoxin from Bacillus thuringiensis induces systemic and mucosal antibody responses in mice.

After intraperitoneal injection, lethality is observed at 326.4 μg/kg in rats and 83.1 μg/kg in ferrets [3, 4].

The cocaine LD50, for instance, was obtained by IP (intraperitoneal) injection, while the caffeine administration was oral.

Finally, fasting and intraperitoneal injection of β-HB upregulate Oct4 and Lamin B1 in both vascular smooth muscle and endothelial cells in mice in vivo.

I've found a datasheet[0] that lists an intraperitoneal LD50 of 115 mg/kg in mice.

> For vitamin C experiments, mice undergoing standard feeding or at the last day of the first FMD cycle started to be treated with vitamin C (4 g/kg in saline) via intraperitoneal injection twice a day, every day until the end of the experiment.

Given the study mice “received an intraperitoneal injection of 2.5x their body weight” [1], it would require heavy at-home DIY doctoring.

"mice receiving a single intraperitoneal injection of tritiated water 7.4 x 10(8) Bq (20 mCi) died of bone marrow failure within 20 days".

Edit: "When pregnancy was confirmed, on days 8 through 14 of gestation [31] the females were administered daily intraperitoneal injections of vinclozolin (100 mg/kg BW/day, Chem Services, Westchester PA, USA)" - not comparable to humans.

The paper goes on to demonstrate the steps they took to minimize the chance that almost-drowning rats resulted in death: "Hypothermia had been suspected as a proximal cause of death [3,31,34] because all SD rats showed an eventual decline in intraperitoneal temperature (Tip); a decline to more than 1 °C below baseline in otherwise untreated SD rats has been a reliable indicator of impending death within a day or two.

Intraperitoneal injection isn't really done in humans, the closest equivalent would be subcutaneous or maybe intramuscular injection.