Frequently Asked Questions

Peptide pens are precision-engineered reusable injection devices designed to hold standard 3ml glass cartridges. They allow for accurate, dial-controlled delivery of your reconstituted peptide solutions, replacing traditional single-use syringes with a durable, consistent tool built for repeated use.

PeppiPens are built to exacting tolerances using high-quality materials. Our V1 Classic Pen and V2 Premium Pen both use the universal 3ml cartridge standard, meaning one set of cartridges and needles works across both models. We focus on simplicity, reliability, and long-term value.

Reusable pens offer far greater precision through a dialing mechanism that allows sub-unit dose control. They are more cost-effective over time, produce significantly less waste, and provide a cleaner, more professional-feeling experience compared to drawing from a vial with a standard syringe each time.

Insert a filled 3ml cartridge into the pen body and secure the cartridge holder. Attach a fresh pen needle. Dial your required dose using the dose selector. Prime with a small air shot if needed. Deliver your dose by pressing the injection button fully.

Using a sterile syringe and needle, draw the required volume of bacteriostatic water and inject it slowly along the inner wall of the vial containing your lyophilized peptide powder. Gently swirl — do not shake. Once fully dissolved, draw the solution into the pen cartridge through the rubber septum.

The V1 Classic Pen is our original model — simple, reliable, and straightforward to use. The V2 Premium Pen features an upgraded dial mechanism with a more tactile click, a refined body finish, and improved grip ergonomics. Both use identical 3ml cartridges and pen needles. See our V1 vs V2 Comparison page for full details.

All standard insulin pen needles with a universal thread fitting (BD-compatible) fit both V1 and V2 pens. We carry 4mm, 5mm, 6mm, and 8mm lengths in various gauges. See our Pen Needles Guide for sizing help.

Both V1 and V2 pens use standard 3ml borosilicate glass cartridges (1.5cm diameter, type 1 glass, bromobutyl rubber plunger and septum). Our PeppiPens cartridges are supplied sterile and individually sealed for single-fill use.

Our travel cases are designed to hold one fully assembled pen, 2–4 spare cartridges, a supply of pen needles, and a small cold pack insert. They are insulated, discreet, and TSA carry-on compliant in most jurisdictions.

Store your assembled pen (with cartridge inserted) in a cool, dark location away from direct sunlight. Do not freeze. Reconstituted solutions in cartridges should generally be stored at 2–8°C (standard refrigerator temperature) and used within the timeframe specified by your supplier. Always cap with a needle cover between uses.

Yes. Reusable pens and accessories can generally be carried in carry-on luggage. Liquid solutions in cartridges may be subject to standard TSA liquid rules. We recommend carrying a copy of any relevant documentation and using our insulated travel case to maintain proper temperature during transit.