You can create a complete semester of science lesson plans and chemistry experiments with this shopping list of school supplies from your local pharmacy. Normal science classroom safety precautions should be taken.
Ph test strips or Litmus paper. Use these to test the base or alkaline vs. acid level in products. Find them with diabetic supplies or in school supply catalogs. Or make your own litmus paper using this guide from Owlcation. You'll need blotting paper available from Amazon. Here is a litmus paper color chart to indicate acid or alkaline (base). 
Assorted vitamins and pain relievers: Give each student a label from different medicines and vitamin bottles. Have them analyze the ingredients for additives, active ingredients, composition, dyes, etc. Students can also evaluate safety, effectiveness, proper usage, etc. Students should compile a medicine safety booklet.
Pill solubility chemistry experiments. Demonstrate how long it takes various pills to dissolve and enter the bloodstream. Students should note findings in science journals.
Medicines in water source chemistry experiments. Extend pill solubility lesson plans into an ecology lesson by allowing the water to evaporate. Note any remnants of the pills. Explain how flushed pills and medications enter our environment via sewer systems and are spread to rivers, lakes and streams. Via the water cycle, they enter the atmosphere.
Glycerin science experiments: Glycerin is basically biodiesel fuel. It has a sweet taste and it used to coat pills to make them taste better and easier to swallow. Debate with students the advisability of using an alcohol based product for ingested products. This thick liquid can also be used to demonstrate viscosity of liquids. Demonstrate it by adding it to dish soap and water to make super sturdy bubbles.
Soap chemistry lesson plans. Compare ingredients with commercial soap brands which claim to be pure and gentle. Ivory, Dove, Caress to castile soap and other natural soaps. Compare ingredients in stronger soaps like Irish Spring, Lava and Fels Naphtha. Use ph strips to test acid or alkaline (base).
Epsom Salts. Here's a complete unit of science activities using epsom salts and other household chemistry supplies. Here are more epsom salts science experiments and craft projects to make crystals, salt, ice, a salt pendulum and more.
Lotions and creams. Use Ph strips to test acidity levels in these creams. Students will be surprised to discover that products that are supposed to soothe and protect often contain very harsh drying chemicals like petroleum or alcohol.
Isopropyl Alcohol: Have fun with this non-Newtonian liquid. That's one that doesn't follow the laws of physics. Rubbing alcohol is used to dry up or evaporate other liquids. Hand sanitizer is a great example as it dries quickly. Alcohol is used for swimmer's ear to keep the ear from holding water and to dry it quickly. In fact consumed, beer, wine or liquor alcohol dehydrates the body.
Hand sanitizer. With Covid 19, we're using more antibacterial hand sanitizer. Demonstrate to students that while it kills bad germs it's also dangerous because it kills all bacteria, even good bacteria. It's also somewhat flammable.
Iodine. Iodine has disinfectant and anti-puritic capabilities. It is yellow in color, but will turn deep purple in the presence of a starch (bread, potato, etc.). Iodine can be used in numerous science lesson plans on anatomy, biology, nutrition, chemistry and health.
Hydrogen Peroxide. Women used to "bleach" their hair with peroxide. Use to demonstrate whitening properties by pouring on a lock of cut hair. Use peroxide toothpaste to show how it removes stains from teeth. Remove stains from clothing with peroxide. It is the base of oxy cleaners. It will also foam up when applied to a cut, to clean away dirt. Benzoil Peroxide cleans out pores. Hospitals use betadine now instead of peroxide.
Syringes. Use to demonstrate a vacuum. Teach measurement and use to add drops of liquid.
