If you do lose some weight while receiving lipotropic injections, this is likely more due to other factors in your weight loss program like exercise and diet than to the shots alone
There are even recent studies that have found metformin to have protective and therapeutic effects against COVID-19 (Bramante et al., 2021, 2023)

INTRODUCTION AND AIM Diabetes mellitus (DM) is one of the metabolic disorders with high prevalence.[] With more than 536.6 million cases in 2079-year-olds having been diagnosed, diabetes prevalence is reported to be 10.5% in 2021 globally and it is estimated that the number will rise to 783.2 million in 2045.[] Complications of DM are rising all over the world[ , ] and are accounting for 520% of healthcare budgets in most countries and even in some developing countries.[] DM remains one of the main causes of myocardial infarction.[ , ] Recent studies have shown a direct connection between levels of some plasma lipid profiles such as HDL cholesterol (HDL-C) level and apolipoprotein B (Apo B), apolipoprotein A1 (Apo A1), and some cardiovascular complications such as thoracic aortic atherosclerosis.[] These studies emphasize the importance of total cholesterol (TC) or LDL cholesterol (LDL-C) in raising the risk of cardiovascular disease in individuals with diabetes, which support the current recommendation to reduce LDL-C to prevent the onset of atherothrombotic vascular events in them.[ , ] In patients with type 2 diabetes, the LDL-C catabolism is significantly reduced,[] resulting in an increase of the duration of the presence of LDL-C in the plasma, which itself may increase lipid deposition in the arterial wall

The dose-response is real, and the desire to find a sweet spot below 5 mg is understandable for someone tolerating 2.5 mg fine but suffering at 5 mg
Why Should You Prefer Sublingual Absorption of Glutathione