Assalam Alaikom,
I'd like to ask for fatwa about something called " shellac "
shellac is just from some insect that produces this sticky stuff for its cocoon. It's used in making pills and glues and insulators and sticky sweets. It sounds like it's in all the pills of medication we take but I read it gets dissolved in alcohol so I was so worried, is it prohibited? Would you please help me with that? Thanks

The legal ruling for this issue is based on the effect of Istihala in removing a substance's impurity [najasa] and thus rendering it permissible for human consumption.

Meaning of Istihala:

Istihala means the transformation of a substance's properties resulting in the removal of its impure nature. After their transformation, such substances are no longer designated as impure.
Substances such as those derived from the shell of this kind of insect mentioned in the question undergo chemical and physical processes which completely change their chemical composition and transform them into colorants. Through this process, these substances become pure and permissible for human consumption provided they are not harmful to health. This is the opinion of the majority of scholars who maintain the impermissibility of eating insects because they are considered filth or impure.

The Maliki opinion on eating insects:

Contrary to the majority of scholars, the Malikis have permitted human consumption of insects provided they are ritually slaughtered. According to them, this occurs by any means that lead to their death. Examples of scholarly opinions include:

- Ibn al-Hajib in Jami' al-Ummahat (p.224) said: "It is permissible to eat vermin of the earth after slaughtering them in the same manner as locusts. It is permissible to eat the food upon which vermin falls and to eat the worms found in food (along with the food itself”.)
- Ibn Rushd said in Al-Bayan wa At-Tahsil (vol.3, p.306): "Scholars differed over eating locusts. Some maintained that it is not necessary to slaughter them before eating and it is permissible to eat them if they are found dead. Others maintained that it is obligatory to slaughter locusts before eating them. They agreed that they can be slaughtered by any means that causes their immediate death such as cutting off their heads, striking them with needles or thorns, throwing them in fire or hot water and the like. However they differed over methods that do not cause immediate death such as cutting off their legs, wings or throwing them into cold water and the like. This is because Sahnun, the Maliki scholar and others did not maintain the necessity of their ritual slaughter. Ibn Habib, on the other hand, said that capturing locusts is tantamount to slaughtering them. They may be eaten if they die without slaughtering them in any manner." 
- In Ash-Sharh al-Kabir (vol.2, p.115), Abu al-Barakat Ahmed al-Dardir gave examples of insects permissible for human consumption: "It is permissible to eat scorpions, beetles, cockroaches, grasshoppers, ants, worms, mites, ticks, geckos, lizards and Sand fish which is impure when dead and only becomes pure after slaughtering."
The ruling
It is permissible to add this substance to medicine and foodstuff provided it has not been proved to be harmful to human health.