Why do some medications come in tablets and others in capsules? Why are there ointments and creams? And why are some drugs delivered by injection or through an intravenous (IV) drip?
Like a lot of things in medicine, the answer can get complicated, but it boils down to this: where a drug needs to be, how quickly it needs to get there, and how long it needs to hang around. After a major surgery, your doctor could prescribe a powerful painkiller by IV drip, which gets the drug circulating right away, and to pain receptors throughout your body. But if you have a chronic condition, IV isn’t convenient – you probably don’t have time to sit for an hour after breakfast and before bedtime while medication drips slowly into your veins. So an oral formulation, like a tablet or a capsule, is better.
To get a sense of which formulations work for which purposes, it helps to think of the form — a pill, an ointment, or an injectable — as a vehicle, and the drug itself as a passenger along for the ride. Here’s a primer.
The passenger: The drug
The most important part of a medication is its active ingredient, such as ibuprofen for pain relief or rosuvastatin for cholesterol control. It is the drug (or chemical) that creates a therapeutic response in your body. How the drug gets where it’s going safely, and at the right speed, is the job of the vehicle, made of non-therapeutic inactive ingredients (also called excipients) that facilitate transport and uptake.
The vehicle: The dosage form
In a tablet, the drug is combined with substances to give the tablet its shape, texture, and color. These inactive ingredients keep the drug chemically stable so it can be shipped and stored, and they help dictate the way the pill is digested in your stomach and intestines, freeing the active ingredient. Tablets are durable, which is why so many medications come in tablet form. They can withstand the physical pressures of a pill bottle or your pocket, protecting the drug. They’re kind of like the transport truck of dosage forms.
An injectable medication, on the other hand, conveys the drug in a liquid form along with inactive ingredients. After injection, the fluid flows readily into the bloodstream (or body tissues) and the drug is easily freed. It’s more like a motorcycle: there’s not much protection for the passenger, but the ride tends to be faster and purer.
The road: Our bodies
Each drug needs to get from where you take it (the site of administration) to its ultimate intended destination (the site of action). The site of action might be as localized as a patch of skin or a particular organ, or as dispersed as chemical receptors found throughout your body. For example, morphine, a strong painkiller, acts on receptors found in the brain, spinal cord, limbic system, and even in your digestive tract.
Many medications need to get into the general circulation of fluids in your body — the bloodstream, in particular — in order to flow to their sites of action. Ideally, 100% of a drug gets to its destination. In practice, most medications need to pass through multiple barriers in your body (biologic membranes) and undergo a complex series of biochemical reactions along the way, some of which “use up” a portion of the active ingredient.
When a medication is given intravenously, it enters the circulation directly and is considered 100% available to your body. When taken by mouth, it has to go through part of your digestive system first. Only some of the drug makes it to the site of action; the rest is effectively processed as waste. This concept is called bioavailability: the portion of the drug that actually makes it into your circulation.
Choosing the right ride: Different forms for drugs
When scientists create medications, they choose a dosage form that marries biochemistry with convenience. The drug needs to do its job effectively and safely, but the medication has got to be practical, too. There are dozens of common routes of administration and dozens of dosage forms: patches that deliver drugs through the skin, solutions that are injected not just into veins but into muscles, beneath the skin or directly into organs, and liquids that are meant to be dropped into eyes and ears.
The most common oral dosage forms are tablets, capsules, and liquids.
- Tablets and capsules: In tablets and capsules, drugs are distributed as a chemical salt which keeps the active ingredient stable and solid. Both can be engineered to time-release medications more quickly or more slowly. Soft gels are a kind of capsule that transport the drug in a liquid form, digested more quickly, so the active ingredient can reach circulation faster.
- Liquids: Medicines like cough syrups feature their active ingredients in a liquid suspension or solution that’s easily bottled, meant to be swallowed — and, unfortunately, tasted. While it’s possible to deliver cough and cold medicines in tablets, it’s easier to imagine relief of a sore throat coming from a syrup than a pill. Conversely, many medicatio
- Oral disintegrating tablets (ODTs): Sublingual dissolving tablets are placed under the tongue and broken down by enzymes in your saliva, allowing the drug to absorb through the tissues in your mouth. Some medications come in this form as an alternative for people who have trouble swallowing pills. ODTs generally act faster than swallowed tablets.
- Release schedules: You may have seen words like regular release and extended release associated with medications. Extended or sustained release meds are chemically engineered to release the active ingredient at a particular rate, usually to keep the level of drug in your system steady and to increase convenience: instead of taking a pill every six hours, you might be able to take it every 12 hours instead. Sometimes the combination of active and inactive ingredients changes substantially to achieve the desired performance.
- The mystery of giant pills: Why are some tablets just huge, while others are positively tiny? Mostly because certain chemical properties of a drug require enough other ingredients to regulate how the tablet is digested. In other words, a big tablet might be the result of all the “stuff” that keeps the pill, and all the drug in it, from dissolving in your digestive system too soon, releasing the drug at the wrong place and the wrong time.
Nasal and oral inhalation
Breathing a drug in through your nose or mouth is a quick way to get a drug into your system: your airway and lungs have a lot of surface area to absorb the drug. Some drugs go to work right in the airway, so inhaling them gets them where they need to go, such as drugs that treat bronchial problems or asthma.
Drugs packaged for inhalation may come in liquid, solid, or gaseous form, assisted by all manner of useful excipients. Nasal anti-inflammatory drugs like fluticasone are distributed in spritzers that mist droplets of the drug into your nose for inhalation. Inhalers for treating asthma commonly employ two forms: the drug aerosolized in a chamber along with a propellant that forces it to spray out of the inhaler, or as a fine dust (dry powder). Anesthetic drugs used to “put you to sleep” before surgery are frequently given in gaseous form — a few breaths and you’re out cold. Laughing gas, or nitrous oxide, is another drug famously given as a gas.
Topical medications — commonly liquids, creams, or ointments — are applied directly to a surface, like your skin, right at the spot they’re needed. And because they don’t go through the digestive system, they tend to have fewer systemic effects or side effects.
Many ophthalmic drugs are also topical — for obvious reasons, liquid is a suitable form for eye drops. But why can you get the same medication, like clobetasol for treatment of psoriasis, in all three forms? Well, you wouldn’t want to rub a cream or ointment into your scalp if you’ve got a full head of hair. And while water-based creams readily absorb, getting the drug into the skin quickly, your particular condition might need a slow-and-steady release of medication; an oil-based ointment doesn’t absorb so easily and will “hang around” longer, letting the drug diffuse more slowly into the skin.
Transdermal patches are another form of topical medication, commonly used for nitroglycerin to treat angina, nicotine patches to help people quit smoking, and for some pain and birth control drugs. They may deliver a drug close to where it’s needed, but more commonly are used to deliver a steady dose of medication over a lengthy period of time — one that doesn’t go through your digestive system. Because these drugs bypass metabolism in the liver, this form is suitable for drugs like nitroglycerin, ensuring high bioavailability.
Many drugs are administered by injection. They’re distributed in a liquid solution or suspension and injected into a vein, organ, or tissue — wherever the drug is needed, or the best place to get it circulating.
Other drugs are injected between layers of skin (intradermal), into muscle tissue (intramuscular), or, in hospitals, even directly into organs like the heart (intracardiac) or brain (intracerebral). An ophthalmologist might even inject a medication directly into the cornea of the eye, in an intracorneal injection. These injections get a dose of drug straight to the site of action.
What does this all mean?
As you can see, medications come in many forms and there are just as many reasons for such. There is a whole discipline — pharmacokinetics — concerned with the biochemical journeys taken by drugs.
But for the average patient, the only time we need to think about different medication forms is if the treatment we were prescribed is not working well enough or if it’s too expensive. Not every medication comes in multiple forms, but you can ask your doctor (or check GoodRx) if they have another recommendation for you.
One of the biggest downsides to taking a medication is side effects. After a dose of most drugs, the amount in the bloodstream spikes quickly, and then is flushed away within the course of a few hours. This means the amount of medicine in the body can vary at any point in time – and that spike can mean nasty side effects.
This problem is exactly what extended release (often noted as ER or XR) drugs were designed for. Typically taken once a day, these formulations keep the therapeutic dose at a steady level in the body for longer periods of time. So if you’re not getting the response you want from your current medication, it may worth talking to your doctor about trying an XR version. But bear in mind: the XR formulation can often be much more expensive.
How do XR drugs work?
Drugs are usually broken down by the liver or kidneys, which means that after taking a dose, the body begins to naturally clear the medication from the system. As their name suggests, XR drugs typically include special coatings or mixers that make the drug take longer to clear from the body than ordinary or immediate-release (IR) drugs. Many popular drugs are now available in XR; there are well over 30 for pain alone.
The graph below shows blood concentrations of the pain medication Ultram (tramadol) after taking the immediate-release version (the white dots) every six hours, compared to the extended-release version (the dark dots), taken once every 24-hours.
Notice how the amount of drug in the bloodstream spikes for the IR drug. XR drugs eliminate this problem. Though they typically have a slightly slower onset compared to their IR counterparts, they maintain a more consistent level of the drug in your body, which could mean better treatment outcomes for longer periods of time while also lowering the occurrence of side effects. You also don’t have to take the drug as often, which may mean that you are less likely to forget to take your medication, especially when multiple doses are needed throughout the day.
But about that price
So why doesn’t everyone just take the XR versions? Usually because of the price. Typically, XR formulations go through a new drug approval process with the FDA and are granted an additional patent as a new drug. This means that an XR version often doesn’t have a generic alternative, making it more expensive – and giving the drug company more time to make more money. This is why new extended-release versions of popular drugs turn up just before the patent expires (such as a new version of Lyrica). Some XR drugs – such as Adzenys or Concerta, for ADHD; or Zohydro for pain – can be nearly 10 times as much as generic alternatives.
But that’s not always the case. Extended release versions of alprozolam (Xanax) and metformin (Glucophage) are available in generic form, and aren’t much more than twice their regular version. Depending on how often you take your medicine, these versions can actually be cheaper than the old versions when you factor in the number of pills. Also keep in mind that some health insurance plans will only cover traditional immediate release drugs, so call your pharmacist or insurance provider – and check GoodRx – to check the price first.
Are XR drugs right for me?
If you are taking prescription meds every day, you should work with your physicians to ensure you’re taking the right form of medication for you. This may mean tracking your side effects and getting blood tests to get a better handle on what the highest and lowest concentrations of the drug is best for you personally. There’s also a small chance that your body might not be able to break down the slow release coatings or ingredients fast enough to hit that targeted therapeutic level in the bloodstream, so be sure to go back to your doctor if you don’t think it’s working.
Why is Synthroid (levothyroxine), a medication that treats thyroid hormone deficiencies—or hypothyroidism, as it’s called—the number one drug in terms of the number of prescriptions written by physicians?
It’s easy to understand why atorvastatin would be on the list. For years, widespread marketing has flooded with TV commercials and website ads for statins as a means (after changes in diet and exercise) to treat high cholesterol. And high cholesterol leads to heart disease, which is the biggest cause of death in the US. So yeah, there are going to be a lot of prescriptions for that.
But a synthetic hormone for thyroid problems — do that many people have serious issues with their thyroid gland?
Causes of hypothyroidism
Let’s start with some basic biology. Normally, the thyroid gland secretes hormones that help regulate metabolism and adjust how fast the body uses energy. With hypothyroidism, the thyroid gland cannot produce enough hormones naturally, so a drug such as levothyroxine replaces what the body doesn’t make itself.
The most frequent cause of hypothyroidism is an autoimmune disorder known as Hashimoto’s thyroiditis, which can occur in 0.15% of the population each year, and can be up to 10 times more common in women than in men. With Hashimoto’s thyroiditis, the immune system attacks the thyroid gland, creating inflammation and decreasing hormone production. Treatment with levothyroxine corrects the problem. Another possible cause of low amounts of circulating thyroid hormones is thyroid cancer, which affects 1.1% of people in the U.S. sometime during their lifetime, and accounted for 3.8% of new cancer cases in 2014. If a large enough tumor engulfs the thyroid, or the gland itself is surgically removed, the levels of the hormones it produces drop. Patients, then, require medication — such as levothyroxine — to boost the amount of circulating hormones back to normal. Still, that means about 5 million Americans need levothyroxine during their lifetime, not per year. So what else might be going on?
Is the rate of thyroid cancer increasing?
According to the Surveillance, Epidemiology, and End Results (SEER) Program, the overall incidence rate of thyroid cancer is on the rise, which may at least partially explain why there are so many prescriptions for levothyroxine written each month. In fact, according to the SEER report, the number of thyroid cancer cases has been increasing 5.5% per year in the U.S. over the last 10 years.
However, a New York Times article questioned whether the apparent increase of thyroid cancer was real or just an artifact of better detecting the disease, such as through ultrasound imaging or needle biopsy of the thyroid. More cases detected doesn’t necessarily mean more people actually have the disease. But it would help explain why there are so many prescriptions.
So is there detection bias here? Let’s look at the death rates over the same period of time. At first blush, the SEER data on thyroid cancer seem to show that the number of deaths from the disease is flat, fueling critics’ assertions that the increased rate of thyroid cancer detection is due to better diagnostics. But upon closer examination, that isn’t quite the case, mostly because there is a discrepancy in the death rate when you separate the data based on certain factors. (For biostats geeks, more details on the why in the endnote*).
Quick check: Are people searching for information on thyroid disease online?
The popularity of levothyroxine prescriptions is even more confounding when you look for other signals of demand, such as search activity on Google. Search Google Trends and you’ll see that the volume for thyroid-related searches is relatively low compared to other predominant conditions. “Thyroid” and “hypothyroidism” searches occur much less frequently than, say, searches for “depression” or “Hypertension.” Of course, the demographic most affected by thyroid disorders tends to be older, which, according to a Pew Internet study, means that fewer may be searching online for medical information compared to their younger counterparts. Conversely, there is a much larger age span of people affected by hypertension and major depression that could inflate the search volume for these conditions.
Bottom line: levothyroxine works
So what’s the answer? Why is levothyroxine so popular? Maybe it’s just that it seems to work very well. In survey data from Iodine.com, based on over 1,000 people who are taking (or had previously taken) levothyroxine, about 84% of women said that the drug is worth it for them. This demographic nearly coincides with the most common hypothyroidism patient profile: women with a median age of 50.
So put these together and you have a fairly clear hypothesis: high satisfaction with the treatment combined with growing cancer rates combined with higher diagnosis rates equals a lot of people taking a lot of one hormone drug.
One last wrinkle: Many people have concerns that the generic version of levothyroxine doesn’t work as well as the branded Synthroid version. These concerns are especially acute for people whose insurance may not cover the brand drug – which is can be two or three times more expensive than the generic version. Since these are hormones, the two versions are not entirely interchangeable; there has been much controversy over the issues of “bio-equivalence.” Ultimately, it’s important to work with your doctor to find the best drug that works for you, including affordability.
*Endnote: First, gender: Five years after thyroid cancer diagnosis, survival rates for women increased 4.7% from 1974 to 2001, while death rates in men increased by 2.4% from 1992 to 2000. If the increase in incidence rate of thyroid cancer was simply due to better diagnostic tools, proponents argue, we wouldn’t see this dichotomy between female and male survival rates.
Second, geographical location: Healthcare professionals are seeing an increase in thyroid cancers outside of the U.S., in countries that don’t have access to the advanced diagnostic tools that are commonplace in American hospitals. This supports the hypothesis that there is a legitimate increase in the number of thyroid cancer cases not just in the U.S., but worldwide. Last, 10-year survival data: Unlike the 35-year survival data shared by the Center for Disease Control (CDC), looking at thyroid cancer over 10 years shows that death rates from the disease have increased at 1.2% per year from 2001 to 2010, making thyroid cancer the second fastest growing cause of cancer death (liver cancer tops this category). Most other cancers, by contrast, had a decreasing death rate over that decade.
Watch out—birth control is getting political again. And even if you avoid politics, you’ll want to pay attention.
Recent changes to the Affordable Care Act mean that employers are no longer required to cover birth control as part of preventative care. This means that if you’re a woman and have health insurance through your employer or school, like Catholic university Notre Dame, your access to contraception may disappear in the next few months. (Women taking birth control for a medical condition will not be affected, only those using it for pregnancy prevention.)
If you’re currently taking birth control and your coverage does end, don’t panic. Chances are GoodRx has discounted prices for the type of birth control you’re on, so you don’t have to pay the full retail price out of pocket.
Here’s what to do if . . .
You’re on the pill
- Search for your pill on GoodRx. There are hundreds of oral contraceptive brands out there, and GoodRx offers savings for a majority of them – and almost certainly the most commonly prescribed options.
- If you’re on a brand-name version of the pill, call your doctor to see if they can switch you to the generic form as generics tend to be 70-80% cheaper.
- Popular birth control pills: tri-previfem ($8.92), orsythia ($14.92), junel FE 1/20 ($15.17), camila ($8.91)
You’re using the patch or the ring
- These are monthly costs so you may want to consider switching to another type of birth control if it is too expensive in the long run.
- GoodRx can save you 38% on the patch (Xulane, $86.21) and 11% on the ring (NuvaRing, $149.98).
You’re taking the shot
- The generic version (medroxyprogesterone, $43.54) costs 60% less with GoodRx—and lasts 3 months at a time.
You have an IUD or implant
- Implants last 4 years and IUDs last 3 – 12 years (depending on the type of IUD you have) so you’re probably protected for a little while longer.
- If you do have to get your contraceptive device removed soon, the procedure itself can cost up to $300. Contact your local Planned Parenthood health center as they may charge you less, with or without insurance.
- After removal, you can look at other birth control options to continue preventing pregnancy, and save with GoodRx.
Prices shown are average GoodRx discounted prices as of Nov 2, 2017. Local results may vary.
Last month, the Trump administration rolled back part of the Obamacare contraception mandate, making it no longer mandatory for employers to cover the full cost of birth control on grounds of religious freedom. 55 million women who received free birth control since 2012 are now at risk of losing it. Employers are now free to remove birth control coverage from their employee insurance offerings, and hundreds of thousands of women might be at risk of losing free birth control.
Now is a good time for women to understand their options, in order to find affordable out-of-pocket protection, as well as a method that won’t wreak havoc on their bodies either. Here is some useful information about oral contraceptives – also known as “the pill” – which are the most popular forms of birth control. (If you already know the pill isn’t right for you, see this birth control tool which includes information about IUDs and other methods).
Top 5 prescribed brands (and their generics)
About 90% of the birth control pills used in the U.S. are generic versions of brand-name drugs. The brands are usually still available, but they’re generally much more expensive than the generic alternative. Here are the 5 most commonly prescribed oral contraceptives in the United States, in both brand and generic form:
- Ortho Tri-Cyclen ($50.15); generics tri-sprintec ($9) and tri-previfem ($8.92)
combination triphasic pill
- Alesse (discontinued); generics orsythia ($14.92) and aviane ($14.91)
combination monophasic pill
- Loestrin FE 1/20 ($118.05); generic junel FE 1/20 ($15.17)
combination monophasic pill with iron
- Nor-Qd ($67.25); generics camila ($8.91) and norethindrone ($9)
progestin-only / mini pill
- Desogen ($52.04); usually dispensed as generic apri ($15.64)
combination monophasic pills
Prices shown are average GoodRx discounted prices as of Nov 1, 2017. Local results may vary.
How do doctors decide what to prescribe?
The conversation usually starts with a doctor asking what their patient would feel most comfortable using. If they aren’t sure or don’t have a preference, the doctor typically starts with Ortho Tri-Cyclen for adult non-smokers under 35, Loestrin Fe 1/20 for teenagers and young adults, and camila for women who smoke, are breastfeeding, or are over 35.
How do I know if I should switch?
Most oral contraceptives will effectively prevent pregnancy when used properly (the pill has a failure rate of 9% with typical use), but they can also cause a lot of unpleasant side effects. After all, taking the pill means adding hormones to your body – and everybody reacts differently to hormones. So know that what and how you’re feeling may not always match the guidelines, and know too that there are usually other good options. The most common reasons women switch are menstrual cycle changes (flow becoming too heavy or irregular), weight gain, acne, headaches, and mood changes. It can take your body up to 3 months to get used to the new hormones, so don’t be afraid to talk to your doctor about other options if these side effects don’t get better after a while.
What kind of hormones are we talking about?
It only requires one hormone, progestin, to prevent pregnancy. On its own, progestin stops ovulation to prevent fertilization, thins the uterine lining to prevent implantation, and thickens the cervix to prevent sperm from entering the uterus. Estrogen helps boost the contraceptive effects of the progestin, and also helps to prevent ovulation. Its main purpose, though, is to help provide better cycle regulation. The more estrogen there is, the lower the chance of breakthrough bleeding or spotting.
Why are there so many different brands?
In a nutshell, each brand contains a different combination of progestin and estrogen meant to help women minimise side effects while effectively preventing pregnancy. Progestin, unlike estrogen, does not increase the risk of stroke and is safe to use while breastfeeding. But you have to take it at the same time every day or else you risk getting pregnant and experience breakthrough bleeding. For this reason, some women opt for brands that also have estrogen — so there is more flexibility to remembering to take the pill. Estrogen is also better for cycle regulation but comes with a lot of side effects attributed to birth control, like lowered sex drive, acne, bloating, weight gain, and mood swings.
Your doctor will work with you to figure out what levels of progestin and estrogen are best for you, but it’s useful to know your options ahead of time. Below, we go into more detail about all the available types of oral contraceptives and how they may affect you.
A “combo” pill contains both progestin and estrogen. Most birth control pills fall into this category, but there are several sub-categories as listed below:
- Monophasic pills are the most common type of birth control pill. They are “single phase”, meaning they provide a steady dose of hormones throughout the entire pack. Doctors will usually start women on a low dose of estrogen to limit the risk of stroke, and switch to a higher dose if they experience too much breakthrough bleeding or spotting.
- Biphasic pills contain two sets of pills at different strengths. Usually, the amount of progestin changes and the amount of estrogen stays the same throughout the entire pack until you get to the inactive, or placebo, pills.
- Triphasic pills provide a steady dose of estrogen but three different doses of progestin throughout the pack. The level of progestin gradually increases as you go through the pack similar to what the body does naturally. The most common pattern is 7 days of one strength, 7 days of another strength, 7 days of a third strength, and then 7 days of inactive pills.
- Quadriphasic pills contains four different strengths of hormones and is supposed to be the best at imitating a woman’s natural hormone changes throughout her menstrual cycle.
- Pros: Side effects and breakthrough bleeding are least likely to happen on this type of combo pill
- Cons: Missed pills are very hard to correct, meaning that a woman is more likely to get pregnant by accident if she misses a dose
- Examples: Only one brand available, and it’s expensive — Natazia ($192.92)
- Extended cycle pills are designed to deliver hormones for 91 days so women only have 4 periods a year. They usually come as monophasic pills but there are a few triphasic options as well.
- Pros: Good option if you want fewer periods (for personal or health reasons) or want to adjust your periods for life events
- Cons: Because it changes your natural cycle so dramatically, you are very likely to experience breakthrough bleeding or spotting
- Examples: jolessa ($48.18), camrese ($50.11), camreselo ($74.15)
- Continuous cycle pills are similar to extended cycle pills except there are no periods at all. You can do the same thing with your regular monophasic packs, though — doctors often instruct women to take only the active pills in the pack and continue on to the next pack without any breaks.
- Pros: Virtually eliminates menstrual periods and reduces cramps
- Cons: Extremely likely to cause breakthrough bleeding or spotting. The lack of a period can also make it difficult to know if an unintended pregnancy has happened
- Examples: Only one generic available – amethyst ($29.29)
This is the other major type of birth control pill, commonly referred to as the “minipill”. It provides a steady dose of progestin throughout the month. It doesn’t contain estrogen, there are no inactive pills, and you don’t take a break between packs.
- Pros: Best choice for smokers, women over 35, women with a history of strokes or heart problems, and breastfeeding women
- Cons: The minipill is very unforgiving — you must take it at the same exact time every day. If you miss a dose by 3 hours or more, you can get pregnant and you are very likely to have heavy breakthrough bleeding
- Examples: camila ($8.91), jolivette ($8.91), norethindrone ($9)
The name game
Brand name pills are usually pretty simple to pronounce and remember. Some are even pretty clever. Loestrin, for example, prides itself on providing the lowest amount of estrogen compared to other brands. Ortho Tri-Cyclen is a triphasic pill. With Seasonale and Seasonique, women only get 4 periods a year — so once every season.
Unlike other drugs, the names of generic oral contraceptives aren’t just their chemical names. Manufacturers usually give them special names to make them easier for people to pronounce and remember. While some still try to cleverly play on the type of pill it is (tri-previfem and tri-sprintec are generics of Ortho Tri-Cyclen), most seem random, albeit very feminine (Portia, Zarah, Camila). In general though, birth control pill names can be a bit confusing but we have managed to pick up on a few patterns.
When a number is included in the name, it can mean one of two things. Usually, the number refers to the strength of the hormones in the pack. For example, junel FE 1/20 contains 1 mg progestin and 20 mcg estrogen and Ovcon 35 contains 0.4 mg progestin and 35 mcg estrogen. But sometimes, the number refers to the layout of the pack, so Loestrin 24 FE has 24 active tablets in it. Necon 7/7/7 increases the strength of hormones every 7 days in a pack.
Some manufacturers include a small amount of iron in the inactive pills of the pack, marked by the “FE” at the end of the name (iron is FE on the periodic table). Sometimes women will lose iron during their menstrual period so the extra iron can actually help prevent temporary anemia.
The last thing included in some of the names is “low” or “lo”. Some drugmakers produce a second version of their birth control pill with a lower strength of estrogen than the original. This is a better choice for women who experience issues tied to hormonal imbalances during their cycle (like acne, PMS, and moodiness). On the flip side, LO versions of the pill may not be able to help women who take birth control for acne treatment.
Prices shown are average GoodRx discounted prices as of Nov 1, 2017. Local results may vary. Thanks to pharmacist Christina Aungst for help researching this post.