Self-Administered Penile Injection Therapy

Practical pre-reading for patients who already have a prescription for compounded intracavernosal injection therapy. Your prescriber chooses the formula and dose. Our pharmacy compounds the medication, dispenses supplies, and counsels on handling, storage, injection-site safety, and refill logistics.

This guide does not replace in-person teaching from the urology team or written directions from your prescriber.

Emergency warning: prolonged erection

A rigid, non-bendable erection that lasts too long can permanently damage penile tissue. Follow your written emergency plan. If you do not have a written plan, or if the erection remains rigid and does not resolve, go to the nearest emergency department. Do not go to sleep while still rigid.

Trimix injectable and Trimix gel are not interchangeable

Trimix injectable and Trimix intraurethral gel are different prescriptions with different formulations, strengths, and routes. They must not be interchanged, mixed together, or transferred between syringes.

Do not inject Trimix gel. Do not insert Trimix injectable into the urethra.
Do not use both products within 24 hours of each other.
If you have prescriptions for both, keep them separate and confirm which one you are using before each dose.

Before you start

Your first injection and starting dose should be set by your prescriber or urology team. Do not change your dose, repeat a dose, or combine injection therapy with other ED medications unless your prescriber has given written instructions.

Read the full guide before your first at-home injection. Choose a private, clean, well-lit space where you can focus and where your supplies can stay organized.

Keep a brief log after each injection: date, dose, firmness, duration, side effects, and anything unusual.

Supplies and vial check

What you need

The labelled vial of medication
One new syringe with attached needle
Two alcohol pads
A sharps container
A clean, well-lit surface
Your written prescription directions or dose record

Do not use the vial if

The fluid is cloudy or has floating particles
The rubber stopper is loose, cracked, or missing
The label is unreadable
You are unsure which vial it is

If a vial fails inspection, call the pharmacy before using it.

Taché Pharmacy Trimix Injection Patient Instructions

Drawing up your dose

Wash your hands with soap and water, then dry them on a clean towel.
Wipe the rubber stopper on the vial with an alcohol pad.
Open a new syringe. If the needle touches anything other than the vial stopper, discard it in the sharps container and start with a new syringe.
Pull the plunger back to your prescribed dose marking. This pulls air into the syringe.
Insert the needle through the stopper and push the air into the vial.
Turn the vial upside down. Keep the needle tip below the fluid line.
Draw the medication back to the prescribed dose marking. If bubbles appear, ask us to demonstrate bubble removal during counselling.
Confirm the dose marking before removing the needle from the vial.

Choosing the injection site

The injection goes into the side of the shaft, usually described using a clock face. The common side zones are around 10 o'clock on the left side and 2 o'clock on the right side.

Inject in the middle third of the shaft only. Avoid the head of the penis, the top surface, the underside, and any visible large vein. Alternate sides between injections unless your prescriber has given different written instructions.

Injection steps

Stand if you can. Wipe the selected injection site with a fresh alcohol pad and let it dry.
Hold the syringe like a pencil. If uncircumcised, retract the foreskin.
Gently stretch the penis straight out or away from the injection side. Keep it steady and do not twist.
Insert the needle using the angle taught by your prescriber, typically perpendicular to the shaft at the chosen side site.
Push the plunger steadily while keeping the needle in place.
Pull the needle straight out.
Apply firm pressure with an alcohol pad for 2 to 3 minutes, or longer if your prescriber told you to because of blood thinner use.
Drop the syringe directly into the sharps container. Do not recap it.

After the injection

Stay upright for several minutes after the injection. Do not lie down during onset unless your prescriber gave different instructions.

The goal is an erection firm enough for intercourse that resolves within the expected window from your written plan. Record the dose, response, duration, and any discomfort or bruising.

If the injection does not work as expected, do not inject again that day. Contact your prescriber or urology team before changing dose or timing.

Taché Pharmacy Trimix Injection Patient Instructions

Warnings and urgent symptoms

Do not

Do not inject the head of the penis.
Do not inject the top surface where the nerve bundle runs.
Do not inject the underside where the urethra runs.
Do not inject into a visible large vein.
Do not use a syringe if the needle touches anything non-sterile.
Do not recap a used needle.
Do not repeat a dose because the first dose did not work.
Do not change the dose unless your prescriber has given written instructions.
Do not go to sleep while the erection is still rigid.

Priapism action plan

Priapism means an erection that stays rigid and does not become bendable. It can cause permanent tissue damage.

Follow the emergency instructions your prescriber gave you. Some patients are given a written medication plan for a prolonged erection; others are told to go directly to emergency care.

If the erection remains rigid beyond the threshold in your written plan, or if you are unsure what to do, go to the nearest emergency department.

Who to contact

Call Tache Pharmacy

Vial inspection concerns
Storage, refrigeration, refill, or travel questions
Supply questions, including syringes, needles, or sharps containers
Technique clarification after the prescription has been written

Call your prescriber or urology team

Dose changes
Poor response or response that lasts too long
New pain, curvature, lumps, scar tissue, or bruising patterns
New medication changes

Go to urgent care or emergency

A rigid erection lasting longer than the threshold in your written plan
Chest pain, fainting, or severe allergic reaction
Spreading redness, warmth, fever, or signs of infection

Storage, sharps, and refills

Storage

Follow the label and prescription directions. If a preparation requires refrigeration, keep it refrigerated until use and ask us before travelling with it.

Sharps

Used needles and syringes go directly into a sharps container. Never place loose needles in household garbage or recycling.

Refills

Request refills early enough for compounding time. If your response has changed, contact your prescriber before requesting a dose change.