Testosterone Prefilled Pens: Current Availability
Testosterone prefilled pens are not currently available in the United States or Europe for testosterone cypionate or enanthate formulations. The available testosterone delivery systems include intramuscular injections (requiring manual drawing from vials), transdermal gels, transdermal patches, buccal tablets, nasal preparations, and subcutaneous pellets—but no prefilled pen devices exist for testosterone replacement therapy 1, 2, 3.
Available Testosterone Formulations
The FDA-approved testosterone delivery systems for male hypogonadism include 4, 3:
- Intramuscular injections: Testosterone cypionate or enanthate 50-400 mg every 2-4 weeks, administered via traditional vial and syringe 1, 4
- Transdermal gels: 1.62% testosterone gel at 40.5 mg daily, which is the preferred first-line formulation according to the European Association of Urology 2
- Transdermal patches: Applied daily to non-scrotal skin 3, 5
- Buccal tablets: Mucoadhesive tablets applied to the gum 3, 5
- Subcutaneous pellets: Requiring minor surgical insertion 5
- Long-acting injectable: Testosterone undecanoate 750 mg initially, repeated at 4 weeks, then every 10 weeks 1, 6
Why Injectable Testosterone Remains Vial-Based
Injectable testosterone cypionate and enanthate continue to be dispensed in multi-dose vials rather than prefilled pens or syringes 1, 3. This delivery method requires patients or healthcare providers to manually draw the medication using a syringe and needle for intramuscular administration, typically into the gluteal or deltoid muscle 1.
The intramuscular route produces peak serum levels 2-5 days after injection, with return to baseline by days 10-14, necessitating administration every 2-3 weeks 1. Despite the inconvenience of manual preparation, intramuscular testosterone remains highly cost-effective at $156.24 annually compared to $2,135.32 for transdermal gel 1, 2.
Clinical Implications
For patients seeking more convenient administration without manual drawing from vials, the European Association of Urology recommends transdermal testosterone gel as first-line therapy, which provides more stable day-to-day testosterone levels and eliminates injection-related procedures 2. Alternatively, testosterone undecanoate offers fewer yearly injections (only 4 per year) with more stable levels, though it still requires traditional vial-and-syringe administration 1, 6.
The absence of prefilled pen devices for testosterone represents a gap in available delivery systems, particularly when compared to other hormone therapies like growth hormone or GLP-1 agonists that commonly utilize pen injectors. Patients requiring injectable testosterone must either accept traditional vial-based administration or consider alternative delivery routes such as transdermal preparations 1, 2, 3.