Heart and Circulation Medicines: Names, Classes, Uses and Bleeding Concerns

Introduction

Many heart and circulation medicines share a goal, such as lowering blood pressure. They often reach that goal in different ways. As a pharmacy technician, you need to know three things about each medicine: what it is called, which group it belongs to, and what it is used for. You also need to recognize when a shared goal does not make two medicines interchangeable, and when a patient's report about bleeding needs the pharmacist right away.

This lesson uses five representative medicines: lisinopril, losartan, metoprolol, atorvastatin and warfarin. It is not a complete list of heart medicines.

What you will be able to do

• Match lisinopril, losartan, metoprolol, atorvastatin and warfarin to their class, a main use and a common brand name.
• Explain in plain words how each class works toward its goal.
• Explain why two medicines with the same goal are not automatically interchangeable, and why one ingredient can come in products with different directions.
• Recognize a bleeding concern in a patient taking warfarin, and decide whether it needs prompt pharmacist attention or emergency help.

Before you start: you need everyday reading and arithmetic. Every term is defined here. If you want more practice telling a product's identity apart from its name, see Read a medicine identity before learning a name.

Four words you will use throughout

• Generic name: the name of the active ingredient, the part that does the medical work. Lisinopril is a generic name.
• Brand name: a company's product name for a medicine. Zestril is a brand name for lisinopril. Brand names are capitalized.
• Class: a group of medicines that work in a similar way. Lisinopril is in the class called ACE inhibitors. Knowing the class helps you predict what a medicine does.
• Indication: what a medicine is used to treat or prevent. High blood pressure is an indication for lisinopril.

These words answer different questions. The generic name tells you what it is. The class tells you how it works. The indication tells you what it is for.

Lisinopril and losartan: one goal, two different steps

Plain-English takeaway: both medicines lower blood pressure by stopping a natural signal that squeezes blood vessels. Lisinopril reduces how much of the signal is made. Losartan blocks the signal where it acts.

Start with the problem. Your body makes a substance called angiotensin II. It tightens (narrows) blood vessels. Narrower vessels raise blood pressure, the same way squeezing a garden hose raises the water pressure inside it.

The body makes angiotensin II in steps. An enzyme converts an earlier substance, angiotensin I, into angiotensin II. An enzyme is a body protein that speeds up a chemical change. This one is called angiotensin-converting enzyme, or ACE.

Lisinopril is an ACE inhibitor. "Inhibitor" means it slows or blocks something. Lisinopril blocks ACE, so the body makes less angiotensin II. With less of the tightening signal, vessels are less squeezed, blood flows more easily and blood pressure falls.

• Uses: high blood pressure (alone or with other medicines); heart failure (with other medicines); and improving survival after a heart attack.
• Brand names include Zestril and Prinivil.
• Forms: tablet and liquid taken by mouth.

Losartan is an angiotensin II receptor blocker (ARB). A receptor is the place on a cell where a signal attaches to have its effect. Think of a lock and key. Angiotensin II is the key. Losartan covers the lock. The key may still exist, but it cannot work.

• Uses: high blood pressure (alone or with other medicines); lowering stroke risk in people with high blood pressure and an enlarged left heart wall (left ventricular hypertrophy); and treating kidney disease in people with type 2 diabetes and high blood pressure.
• Brand name: Cozaar.
• Form: tablet taken by mouth.

Why the difference matters: both medicines reduce the effect of angiotensin II, so they share a goal. But they act at different steps, contain different active ingredients and belong to different classes. Each has its own list of uses, forms and warnings. For example, lisinopril's patient information includes a caution about a heart-failure medicine called Entresto, including a 36-hour gap after stopping it. You cannot copy one medicine's warnings onto the other and assume they match.

A study clue for ACE inhibitors. Lisinopril's patient information lists other ACE inhibitors: enalapril, benazepril, captopril, fosinopril, moexipril, perindopril, quinapril, ramipril and trandolapril. Every one of these ends in -pril. Use the ending as a memory clue, then confirm the class. A name ending is a hint, not proof.

A combination product is a different product. Zestoretic contains lisinopril and hydrochlorothiazide. Hyzaar contains losartan and hydrochlorothiazide. A combination product has an extra active ingredient. "It contains lisinopril" does not mean "it is lisinopril."

Question 1

A coworker looks at a losartan prescription and says, "That's an ACE inhibitor, same as lisinopril." Is this correct? Explain using what each medicine actually does.

Metoprolol: a beta blocker, and one ingredient in several products

Plain-English takeaway: metoprolol slows the heart rate and relaxes blood vessels. The heart then works less hard, and blood pressure goes down.

Metoprolol is a beta blocker. Its patient information describes two effects: it slows heart rate and relaxes blood vessels. Together, these improve blood flow and lower blood pressure.

• Uses: high blood pressure, angina (chest pain), heart failure, and improving survival after a heart attack.
• Brand names include Lopressor and Toprol XL.

Same ingredient, different formulation. A formulation is the specific way a product is made: its form, how fast it releases the drug, and how it must be taken. Metoprolol comes in three forms taken by mouth:

• Regular tablet: taken once or twice a day, with or right after meals.
• Extended-release tablet: releases medicine slowly and is taken once a day. It may be split, but the whole or half tablet must be swallowed without chewing or crushing.
• Extended-release capsule: taken once a day. Swallow it whole, without splitting, chewing or crushing. A person who cannot swallow it can open it, sprinkle the contents on soft food such as applesauce, and swallow the mixture right away.

Why this matters: "metoprolol" alone does not identify the product. Each formulation has different directions, so you must match the exact product on the prescription. The patient information lists the brand names but does not state which brand is which release form. Confirm the exact product from the prescription and the package. Do not rely on memory.

One more fact explains why patients should not stop on their own. Stopping metoprolol suddenly can cause serious heart problems. Only the prescriber decides whether to stop it.

Question 2

A prescription is for metoprolol extended-release capsules, once daily. The shelf has metoprolol regular tablets in the same strength. A coworker says, "Same drug, same strength. Use the tablets." What is wrong with this reasoning?

Atorvastatin: a different goal, lowering cholesterol

Plain-English takeaway: atorvastatin slows the body's own cholesterol production. That means less fatty buildup can block blood flow.

Cholesterol is a fat-like substance. It can build up on artery walls and narrow them, blocking blood flow to the heart and brain. A blockage can lead to a heart attack or stroke.

Atorvastatin is an HMG-CoA reductase inhibitor, commonly called a statin. HMG-CoA reductase is an enzyme the body uses to make cholesterol. Blocking it slows how much cholesterol the body makes. This leaves less cholesterol to build up in arteries.

• Uses: lowering cholesterol and reducing the risk of heart attack and stroke.
• Brand names include Lipitor and Atorvaliq.
• Forms: tablet and liquid suspension. These have different food directions. Patients take the tablet with or without food, but take the suspension on an empty stomach.

Notice the contrast with the blood pressure medicines. Atorvastatin also protects the heart, but its target is cholesterol, not vessel tightening or heart rate. "Heart medicine" is too broad a label to tell you a medicine's class.

Question 3

Caduet contains amlodipine and atorvastatin. Is a prescription for Caduet the same as a prescription for Lipitor? Explain.

Warfarin: preventing clots, and why bleeding is the concern

Plain-English takeaway: warfarin makes blood slower to clot. That protects against dangerous clots. It also means bleeding can be harder to stop.

Warfarin is an anticoagulant, often called a "blood thinner." Coagulation means clotting, and anti means against. Warfarin lowers the blood's ability to clot.

• Uses: preventing and treating blood clots, and preventing complications in people with certain irregular heartbeats, replacement heart valves, or a past heart attack or stroke.
• Brand names include Coumadin and Jantoven.

The cause-and-effect link: the effect that prevents a harmful clot inside a vessel also slows the helpful clot that seals a cut. So the main danger is bleeding. Warfarin's patient information carries a warning that it may cause serious bleeding that can lead to death.

Three facts raise or change that risk:

• Other products. Some medicines bought without a prescription, such as aspirin and NSAIDs like ibuprofen and naproxen, can raise bleeding risk with warfarin. Warfarin's patient information also lists herbal products, including garlic, ginkgo, ginseng and St. John's wort, among products that may interact with warfarin. An interaction can change how a patient responds to warfarin, and the patient information does not say that each herbal product affects warfarin in the same way. This is why a patient on warfarin who is choosing a nonprescription or herbal product needs the pharmacist to review it.
• Diet. Vitamin K in foods can affect how warfarin works. Patients are told to keep vitamin K intake steady rather than make sudden changes.
• Dose is set by testing. The doctor adjusts the dose based on a blood test called the INR. Warfarin dosing is a clinical decision. It is never a technician decision.

Same goal does not mean interchangeable

Plain-English takeaway: two medicines can treat the same condition and still be different medicines. Treating the same condition does not let anyone swap one for the other at the counter.

FDA describes a generic drug as a copy of a brand drug. It has the same active ingredient, strength, dosage form (such as tablet or liquid) and route (such as by mouth), and it works the same way in the body. A generic must also be bioequivalent: it delivers the same amount of active ingredient at the same rate and to the same extent as the brand.

Use that definition as a test.

Worked example. A prescription is written for Cozaar. Generic losartan tablets in the same strength have the same active ingredient, form and route. This is the kind of match FDA's generic standard describes.

Change one fact. The prescription is for losartan, but losartan is out of stock. Lisinopril is on the shelf, and both lower blood pressure. Run the test: the active ingredient is different, so lisinopril fails at the first step. It is not a generic for losartan. It is a different medicine from a different class. Changing a patient to a different medicine with a similar use is called therapeutic substitution. The PTCE content outline lists therapeutic substitution among issues that require pharmacist intervention. The technician's job is to recognize the issue and bring it to the pharmacist.

Federal rules and state rules work together. FDA, a federal agency, decides whether a generic is equivalent. FDA approval does not erase state rules. Each state's pharmacy law and your pharmacy's policies govern how substitution is handled where you work. This lesson does not teach any state's specific requirements. Learn the rules for your state and follow your pharmacist.

Question 4

A patient asks to "just switch" from metoprolol to lisinopril because a friend takes lisinopril for blood pressure and pays less for it. What should the technician recognize?

Correct arithmetic does not make a fill correct

Calculations are part of the technician's work, but a correct number answers only one question. (For the method, see Calculate days supply.)

Fictional worked example. Assume a prescription for warfarin tablets, directions "take 1 tablet once daily," quantity 30. The days supply is the number of tablets divided by the tablets used each day: 30 ÷ 1 = 30 days. The arithmetic is correct.

At pickup, the patient mentions they have been taking naproxen every day for back pain. The 30 is still correct, but it does not address the new problem. Naproxen is an NSAID that can interact with warfarin and raise bleeding risk. This is a drug interaction, and interactions require pharmacist intervention. The technician brings it to the pharmacist before the fill is completed.

The tempting mistake: "My math checks out, so the prescription is ready." The math confirms quantity and duration only. It cannot confirm the right product, the right formulation or the absence of an interaction.

Question 5

Fictional case: a prescription is for metoprolol extended-release tablets, 1 tablet once daily, quantity 30. A technician correctly calculates 30 days, but the bottle filled is metoprolol regular tablets. Is the fill acceptable because the calculation is right?

Recognizing a bleeding concern

Plain-English takeaway: when a patient on warfarin describes unusual bleeding, a technician does not judge how serious it is or what to do about the dose. The technician gets the pharmacist right away. If the person's life is in immediate danger, the next step is 911.

Signs that need prompt pharmacist attention. Warfarin's patient information tells patients to call their doctor immediately for signs including:

• bleeding that won't stop, nosebleeds or bleeding gums
• easy bruising
• pink, red or dark brown urine
• red or tarry black bowel movements
• coughing up or vomiting blood, or vomit that looks like coffee grounds
• heavier menstrual or vaginal bleeding
• headache, dizziness or weakness
• a fall with injury, especially hitting the head

Signs of an emergency. The American Heart Association lists severe bleeding, difficulty breathing, unconsciousness and any situation where life is in immediate danger as reasons to call 911 immediately. Warfarin's patient information gives the same instruction if a person has collapsed, had a seizure, has trouble breathing or can't be awakened.

Worked example. A patient picking up warfarin mentions that their gums bleed when they brush and they have new bruises on their arms. Both are listed warning signs. The technician does not tell them to skip a dose or wait and see. The technician gets the pharmacist now, because evaluating an adverse drug event is a pharmacist's job.

Change one fact. A caller says a family member who takes warfarin fell, hit their head and now can't be woken up. Being unable to wake up is an emergency sign. The caller should call 911 now. Then the technician informs the pharmacist.

A symptom does not prove its cause. An adverse event is a harmful or unwanted event that happens while someone is taking a medicine. It is not proof that the medicine caused it. Atorvastatin's patient information also lists unusual bleeding or bruising as a serious side effect. So if a patient takes both atorvastatin and warfarin, a technician cannot tell which one, if either, is responsible. FDA invites reports of side effects even when the reporter is not sure the drug caused the problem. Deciding the cause belongs to the pharmacist and prescriber.

Question 6

A patient taking warfarin asks the technician to recommend a pain reliever and holds up a bottle of ibuprofen. What should the technician do, and why?

Independent practice

Work these without looking back. Explain your reasoning before opening each answer.

Question 7

Match each medicine to its class and one use: atorvastatin, metoprolol, losartan, warfarin, lisinopril.

Question 8

A patient on warfarin calls. They say their urine has looked pink for two days and they feel weak, but they are alert and talking normally. A new coworker says, "It's probably something they ate. Tell them to drink water." What is the right response?

Question 9

A patient who started losartan last week reports dizziness. A coworker says, "Losartan caused it, so they should stop taking it." Identify two problems with this reasoning.

Question 10

A technician says, "FDA has approved this generic as equivalent to the brand, so state pharmacy rules don't apply to substituting it." Is this right?

Question 11

A prescription reads "Toprol XL." Another reads "metoprolol." Without seeing anything else, can you be sure the second is the same product as the first? What do you check?

What to remember

• Name → class → use. Lisinopril: ACE inhibitor, makes less angiotensin II. Losartan: ARB, blocks angiotensin II where it acts. Metoprolol: beta blocker, slows the heart and relaxes vessels. Atorvastatin: statin, slows cholesterol production. Warfarin: anticoagulant, slows clotting.
• Shared goal ≠ interchangeable. A generic must match the active ingredient, strength, form and route. Switching to a different medicine with a similar use is therapeutic substitution, which needs the pharmacist.
• Same ingredient ≠ same product. Release form and combination products change the product and its directions.
• Correct math ≠ ready to dispense. Arithmetic checks quantity only, not product identity or interactions.
• Federal and state rules both apply.
• Bleeding on warfarin: recognize and hand off. Warning signs get prompt pharmacist attention. Collapse, trouble breathing, inability to wake or severe bleeding means 911. A symptom alone never proves which medicine caused it.

For related next steps, see Duplication, interactions and contraindications and Recognize when the pharmacist must intervene.

Review: Organize by the problem being treated

• Lisinopril and losartan: one goal, two different steps
• Metoprolol: a beta blocker, and one ingredient in several products
• Atorvastatin: a different goal, lowering cholesterol
• Warfarin: preventing clots, and why bleeding is the concern