Fifteen years ago, Donna was diagnosed with clots in her lungs. After taking the same blood thinner for over 10 years, she and her doctor decided to stop it. Three years later, after developing shortness of breath, she was given an antibiotic, which didn’t help. Further testing revealed she had new blood clots in both lungs.
The doctors restarted her previous blood thinner and discharged her home. Although her breathing got better over the next few days, she began to itch all over her body and felt “wiped out.”
Donna was in and out of her doctor’s office for the next 3 weeks, trying one allergy medicine after another with no improvement in her itching and fatigue.
When they changed her blood thinner to a different one, her itching and fatigue went away. Could she have developed an allergy to her old blood thinner medicine? Possibly, but there are other ingredients in our medications that can trigger itching, fatigue, or cause our body to absorb them differently.
These “inactive” ingredients are called excipients and lurk in our tablets, capsules, and liquid medicines. There are many choices available, with manufacturers of generic drugs using different excipients than those found in the brand name formulation.
Generic medicines only have to include the same active ingredient as the branded drug. Generics can have different colors, coatings, sizes, shapes, and various “inactive” ingredients. This can lead to differences in how an original medicine acts in your body compared to a generic counterpart.
Tablets and capsules start out with a specific amount of the drug’s active ingredient, usually as tiny crystals of powder. Excipients are added to the active ingredient during the manufacturing process to preserve it, color it, sweeten it,make it easier to manufacture or help it dissolve under your tongue or inside your stomach.
The inactive ingredients lurking in your medicines include dyes, preservatives, diluents, fillers, wetting agents, binders and flavorings.
Stabilizers or preservatives are excipients that protect the final product from contamination from microbes or slow down the degradation of the active ingredient when it’s exposed to oxygen and moisture. Sodium bisulfite is a standard stabilizer added to help an active ingredient stay potent longer. Typical preservatives include sodium benzoate, sorbic acid, and parabens like methylparaben, ethylparaben, propylparaben, and butylparaben.
A diluent is added to active ingredients and coloring agents to blend them evenly. This gives tablets a more consistent color and provides a uniform dose in each whenever pills are cut or broken in half.
With most medicines, combining the active ingredient, diluent, and dye or coloring agent doesn’t provide enough powder to fill out each dose and create tablets big enough to handle easily and swallow. A filler agent like cornstarch, lactose, sucrose, dextrose, or talc may be added to the mixture to create a tablet or capsule of a particular size.
To make a pill easier to manufacture when using an automated pill press, you will need more than your active ingredient, diluent, food coloring, and filler. You’ll need a binder and a lubricant.
A good snowball fight needs snow with enough moisture to help the snow “stick together”when forming snowballs. Dry, powdery snow is fun to ski in, but hopeless when trying to make solid snowballs because it doesn’t stick together when you compress it. A binder gives powdered medicine the “stickiness” it needs to form a tablet when pressed into a particular shape.
When making waffles, you pour batter onto a hot waffle iron and then close it while it cooks. It’s aggravating when your golden waffle refuses to come loose, and you end up peeling each half off the sides of the waffle iron. After pressing a tablet of medicine into its final shape, it needs to drop away so that more pills can be formed. A lubricant is often added to ensure the powdered medication doesn’t stick to the sides of the pill press.
Other examples of excipients are wetting agents, flavoring, and preservatives. Wetting agents are added to pull water into a tablet more quickly. This speeds up the dissolving process for the tablet, releasing its active ingredient more rapidly and completely.
Flavorings are often added to chewable tablets and liquid medicines. Preservatives are added to liquid medications like ear drops, eye drops, and nose sprays to discourage microbial growth.
An inactive ingredient can change how your medicine looks and tastes, can affect how you absorb it, or even trigger an allergic reaction. When you react to a medication, it may not be the fault of its active ingredient but one of its many excipients.
