Things to avoid

• Silicones, they don’t play nice with toys and some can apparently cause uterine cancer
• Petroleum-based products, sticky and generally bad
• Parabens, might mess with hormones
• Anything that can cause a yeast infection, e.g. sugars, honey, glycerin (except ultra pure stuff). Apparently (corn) starch is ok though.
• Any oil, because it can break down latex and is not always toy safe either – however besides that it can work
• Most preservatives can act as irritants, and often are only safe for external use

Things to consider

• pH (water based lubes): for genital use in the range of 4.5 to 5.5, for anal use in the range of 5.5 to 7.5
• Osmolality (water based lubes): should be around 300 mOsm/kg

Oil based formulations

Not for use with condoms and some toys!

I’ve already experiment with a whipped oil recipe, I’ve tried this formulation and it works well. I could experiment with the following:

• Different oils (e.g. coconut, shea, sunflower oil, olive oil)
• Different amounts of starch

Water based formulations

Typical recipe:

• Water
• Humectants. These are the ones I could find that are not on the avoid list:
  • Pure aloe vera
  • PDO (1,3-propanediol) as a vegetable-based replacement for propylene glycol – not well researched
  • However, because of osmolality, perhaps a humectant (other than aloe) is not a good idea anyway
• Gelling agents. These are the ones I could find that are not on the avoid list:
  • Xanthan gum
  • Carrageenan (E407)
  • Hydroxyethyl cellulose – also a humectant
  • Carbomer
  • Agar
• Preservatives, e.g.:
  • Potassium Sorbate
  • Citric acid
  • Sodium Benzoate – might not be safe, but probably fine
  • Vitamin E (Tocopheryl Acetate)
• Other stuff, e.g.:
  • NaOH – to adjust pH
  • Lactic acid – to adjust pH
  • NaCl, KCl, CaCl – to adjust tonicity/osmolality

I could get concentrated aloe with preservatives already added, Xanthan gum and hydroxyethyl cellulose, and then experiment. Perhaps try to reverse engineer BioNude or just try this recipe. Here‘s an overview of some commercial formulations ordered by how safe they are.
All of these ingredients are CG approved, so I could use them for hair products too.

If I want to use both HEC and xanthan, the ratio HEC:xanthan should probably be around 2:1. The xanthan-only recipe uses 0.66% xanthan and 15% aloe. The BioNude formulation does not give percentages, but this HEC-based lubricant uses 1.27% (w/w) HEC and no xanthan, 8.5% (v/v) glycerin, 5.5% (v/v) propylene glycol. Another one uses 1.6% HEC and 20% butylene glycol. I’m thinking to combine this info into the following recipe:

• 10% (rehydrated) aloe
• 10% glycerin
• 1.5% HEC
• 1% Geoguard