HRT Transdermal Spray Tutorial

Transdermal estradiol bypasses liver metabolism and doesn’t require injections. This tutorial explains how to make an estradiol spray bottle which is a convenient way to apply transdermal estradiol and doesn’t require handling gelling agents.

Supplies

Tools (non-consumable):

• Scale
  • 500g (.01 resolution) - Should be fine for sublingual dropper as the target API amount is 4g at the default batch size.
  • 20g (.001 resolution) - If you want to make smaller batch sizes or are worried about precision, use this scale.
  • Weight Boats - Optional, but makes weighing powders less annoying.
  • 5kg (0.01 resolution)
• Glass Beakers
• Glass Stirring Rods
  • The spade and button end version can be helpful for breaking up powder clumps.
• Hot Plate - Used to heat mixture while stirring
  • Version with Automatic Stirring (note: optional and heats slower)
  • Stir Bars for use with automatic stirring version

Consumables:

• 99% Isopropyl Alcohol - The main solvent for the API.
• Isopropyl Myristate - Penetration enhancer to improve bioavailability.
• Polysorbate 80 - Emulsifier to prevent separation of excipients.
  • From Amazon - Note: Amazon version is a cosmetics grade product, whereas SpecializedRx sells NF grade.
• 30mL Spray Vials - Used to store and administer spray.
  • From Premium Vials - Original bottles used. Has high MOQ.
  • From Amazon - Measured at 0.13 mL per spray. (+/- 0.005 mL)

APIs:

APIs can be purchased from Hubei Vanz.

1. Estradiol 50-28-2
   1. 30g $90
   2. 100g $220
   3. 200g $350

Recipe

200mL of 20 mg/mL solution

Ingredient	Percentage	Volume (mL)	Density (g/mL)	Mass (g)
Estradiol				4
Isopropyl Alcohol	45%	90	0.786	70.74
Isopropyl Myristate	45%	90	0.85	76.5
Polysorbate 80	10%	20	1.102	22.04
Total				173.28

Transdermal Progesterone

You can also use this recipe to make transdermal progesterone.

200mL of 60 mg/mL solution

Ingredient	Percentage	Volume (mL)	Density (g/mL)	Mass (g)
Progesterone				12
Isopropyl Alcohol	45%	90	0.786	70.74
Isopropyl Myristate	45%	90	0.85	76.5
Polysorbate 80	10%	20	1.102	22.04
Total				181.28

Procedure

Wear gloves and ensure your workspace is clean. Ensure the beaker and other lab supplies are clean before starting, however with transdermal solutions sterility isn’t as big of a concern as other methods.

1. Weigh out all of the ingredients into your beaker using the recipe above.
2. Place your beaker onto the hot plate at low heat and stir until dissolved.
   1. Isopropyl Alcohol is very volatile. Avoid heating it excessively (ideally do not heat at all) and avoid open flames.
3. Remove the mixture from heat and allow it to cool until you can comfortably touch the beaker with your hands.
4. Fill your bottles with the solution and cap them.
   1. A funnel or pipette may help with this process.

Administration

The solution may separate, so it is important to shake well before use.

Typically people administer 1 full spray every 8-12 hours either on the scrotum or armpit for increased absorption. Each spray is equal to 0.1mL of solution and 2mg of estradiol. Note that the armpit area is near breast tissue which some people may want to avoid and has less absorption. Some people may need to administer two sprays.

Each 30mL bottle contains 600mg of estradiol. At the dosage listed above, a bottle should last 50-150 days. The entire batch should last 333-1000 days.