SleepyCatten<p><span class="h-card" translate="no"><a href="https://mastodon.social/@thejessiekirk" class="u-url mention" rel="nofollow noopener noreferrer" target="_blank">@<span>thejessiekirk</span></a></span> It's not always the case with injections: just the ones that trans masc folk in the UK tend to be given.</p><p>The 2 most-commonly-prescribed injections are:</p><ul><li><a href="https://www.medicines.org.uk/emc/product/5373/smpc" rel="nofollow noopener noreferrer" target="_blank">Sustanon 250</a>.</li><li><a href="https://www.medicines.org.uk/emc/product/14631/smpc" rel="nofollow noopener noreferrer" target="_blank">Nebido 1000 mg</a>.</li></ul><p>Both are compounded at 250 mg/mL, but they're quite different otherwise in terms of chemical make-up, viscosity, and volume.</p><p>Sustanon is a 1 mL injection mix of refined arachis oil (peanut oil) and benzyl alcohol, containing:</p><ul><li>30 mg testosterone propionate</li><li>60 mg testosterone phenylpropionate</li><li>60 mg testosterone isocaproate</li><li>100 mg Testosterone decanoate</li></ul><p>It is typically administered every 2-4 weeks.</p><p>Nebido, conversely, is a 4 mL injection containing 1000 mg testosterone undecanoate, suspended in a mixture of refined castor oil and benzyl benzoate. It's typically administered every 10-12 weeks.</p><p>The main difference between these, other than the different esters of testosterone, is the <a href="https://en.wikipedia.org/wiki/Viscosity" rel="nofollow noopener noreferrer" target="_blank">viscosity</a> of the carrier oil used.</p><p>Figures vary and there's no universal unit used for viscosity, but in all of these, castor oil is <strong>significantly</strong> more viscous than peanut oil, or MCT oil (which is commonly used in the DIY / homebrew community).</p><p>Don't know if this'll help or not, but we thought you might find it interesting :TransHeart: </p><p><a href="https://cultofshiv.wtf/tags/trans" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>trans</span></a> <a href="https://cultofshiv.wtf/tags/transgender" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>transgender</span></a> <a href="https://cultofshiv.wtf/tags/TransMasc" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>TransMasc</span></a> <a href="https://cultofshiv.wtf/tags/testosterone" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>testosterone</span></a> <a href="https://cultofshiv.wtf/tags/Sustanon" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>Sustanon</span></a> <a href="https://cultofshiv.wtf/tags/Nebido" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>Nebido</span></a> <a href="https://cultofshiv.wtf/tags/OpenHRT" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>OpenHRT</span></a> <a href="https://cultofshiv.wtf/tags/DIYHRT" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>DIYHRT</span></a></p>