There is a scientist named Bryan B Fuller (uni of Oklahoma phd) that has several patents for a topical tanning technology.

- Two companies tried to commercialize it (cutanix, therametics), but failed due to problems with formulation among other things. These issues were as far as I know not a safety or efficiency matter.. More a matter of making a product with suitable properties for a consumer-grade lotion (like thickness and consistency)
- He said that the potential efficiency would be melanotan++ and be even more selective for the brown melanin, even for red-heads and type 1s
- The safety would be better than melanotan since it was not going systemic. Disclaimer]- He never divulged the exact tanning agent, but it is found in his patents somewhere
-> Probably not IBMX, but it could work. Some questions about safety for IBMX.
- It was tested on animals (cutanix did animal studies) and a few humans (not officially)
- He used to answer emails about his ideas and the route to a product. Unfortunately he eventually stopped answering requests about his tanner for whatever reason. This was after the second company stopped the project to focus on his skin whitener products.
- It was going to be released as a cosmetic (by avoiding FDA-drug classification ]

Here is a list of Dr. Bryan Fullers skin pigmentation patents. In there somewhere is the main skin pigmentation method that he tried to commercialize and proved effective]* *
5,905,091* * Full-Text* * Enhancement of skin pigmentation by prostaglandins* ]
http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=9&f=G&l=50&co1=AND&d=PTXT&s1=%22fuller+bryan%22&s2=pigmentation&OS=%22fuller+bryan%22+AND+pigmentation&RS=%22fuller+bryan%22+AND+pigmentation


* 5,628,987* * Full-Text* * Pigmentation enhancer and method]
http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=10&f=G&l=50&co1=AND&d=PTXT&s1=%22fuller+bryan%22&s2=pigmentation&OS=%22fuller+bryan%22+AND+pigmentation&RS=%22fuller+bryan%22+AND+pigmentation


* * 5,591,423* * Full-Text* * Pigmentation enhancer and method]
http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=11&f=G&l=50&co1=AND&d=PTXT&s1=%22fuller+bryan%22&s2=pigmentation&OS=%22fuller+bryan%22+AND+pigmentation&RS=%22fuller+bryan%22+AND+pigmentation


* * 5,589,161* * Full-Text* * Pigmentation enhancer and method]
http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=12&f=G&l=50&co1=AND&d=PTXT&s1=%22fuller+bryan%22&s2=pigmentation&OS=%22fuller+bryan%22+AND+pigmentation&RS=%22fuller+bryan%22+AND+pigmentation


* 5,554,359* * Full-Text* * Pigmentation enhancer and method]

http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=13&f=G&l=50&co1=AND&d=PTXT&s1=%22fuller+bryan%22&s2=pigmentation&OS=%22fuller+bryan%22+AND+pigmentation&RS=%22fuller+bryan%22+AND+pigmentation

* * 5,540,914* * Full-Text* * Pigmentation enhancer and method]
http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=7&f=G&l=50&co1=AND&d=PTXT&s1=%22fuller+bryan%22&s2=pigmentation&OS=%22fuller+bryan%22+AND+pigmentation&RS=%22fuller+bryan%22+AND+pigmentation


People tried to make a topical tanner from these patents. Most experimenters did not try long enough, and the agents that were used were mainly theophylline from what I remember reading, and perhaps IBMX.

In here somewhere are a set of methods that will create a nice topical tanner. An added benefit is that the chemicals can be bought with high purity (safety) and not as extracts with impurities.

Some of them have a high price point unless you buy in quantity.