ABSTRACT
In the UK and Australia, testosterone is commonly administered in the form of a fused crystalline subcutaneous implant.6 Subcutaneous testosterone implants are approved for use in postmenopausal women in the UK. The T-implant is inserted subcutaneously in the lower anterior abdominal wall under local anesthetic using a trochar and cannula. The dose commonly initiated is 50 mg. This is achieved by halving a 100 mg implant, which is specifically formulated for use in men. These slow-release implants remain effective for a period of 4-6 months at which time a low free T or total T with SHBG should be confirmed prior to repeat implantation. The dose can be increased in increments of 25 mg to achieve clinical efficacy. However, it is recommended that doses do not exceed 100 mg, as this dose has been shown to result in supraphysiologic serum testosterone levels for at least the first 1-2 months12 and virilizing side effects are more likely to occur above this dose.16 A therapeutic trial of a topical 1% T cream applied daily is often given for 4-6 weeks prior to inserting a T-implant. If there is a positive response, with no adverse effects a T-implant may be inserted.
