8 Neffy (Epinephrine) Interactions and How to Manage Them

If you've had a severe allergic reaction in the past, you've likely armed yourself with an EpiPen (epinephrine) just in case it happens again. But if you dislike injections or have a fear of needles, you might want to consider a new FDA-approved option. It's called neffy (epinephrine). Neffy is a first-of-its-kind epinephrine nasal spray. It treats severe Type 1 allergic reactions, including anaphylaxis. Neffy can be used by adults and children weighing 66 lbs (30 kg) or more.

Neffy is safe and effective to use. But that doesn't mean it's totally risk free. One potential concern is drug interactions. Neffy can sometimes influence the effectiveness of other medications. Or other medications may impact neffy's performance. Be sure to show your medication list to your prescriber or pharmacist so they can check for possible interactions.

Here, we'll discuss eight neffy interactions to know about.

1. Other nasal sprays

Neffy can interact with other nasal sprays. This is because neffy can alter the tissue that lines the nasal cavity for up to 2 weeks after it's administered. This can cause other nasal sprays to be absorbed into the body more than usual. If your body absorbs more of these medications, the risk of side effects can increase.

Nasal sprays for allergies and nasal congestion are some of the most used nasal products. A few examples of over-the-counter (OTC) nasal sprays that neffy might impact are:

• Azelastine (Astepro)

• Mometasone (Nasonex)

• Fluticasone propionate (Flonase)

• Oxymetazoline (Afrin)

• Triamcinolone (Nasacort)

Many prescription products are also nasal sprays. A couple examples are beclomethasone (Qnasl), azelastine / fluticasone (Dymista), and more.

If you recently had to administer neffy, you're at a higher risk of experiencing nasal spray side effects. This risk will go back down a few weeks after administering neffy. Talk to a healthcare professional if you're having any new symptoms that you think may be related to this.

2. Antiarrhythmics and other heart medicines

Neffy interacts with certain heart medications. Namely, those that are used to treat abnormal heart beats. Using neffy while one of these medications is in your system may raise your risk of developing chest pain (angina). It can also raise your risk of abnormal heart rhythms, including ventricular arrhythmias. Untreated arrhythmias can be dangerous.

Antiarrhythmic medications to keep in mind include amiodarone (Pacerone), dofetilide (Tikosyn), and flecainide. Another medication Neffy can affect is digoxin (Lanoxin). It can also interact with diuretics like hydrochlorothiazide (Microzide) and furosemide (Lasix).

Since epinephrine is a lifesaving medication, it's usually recommended to use it when you need it. This applies even if you're taking a heart medication. However, you should still take precautions after administering a dose of neffy. Tell your cardiologist if you recently had to administer neffy. They may want to check in with you to see how your heart is doing.

3. Certain antidepressants

Certain antidepressants may also interact with neffy. Tricyclic antidepressants and monoamine oxidase inhibitors (MAOIs) may amplify the effects of epinephrine. These medications are used to treat depression, Parkinson's disease, and other conditions.

Notable tricyclic antidepressants include:

• Amitriptyline

• Clomipramine (Anafranil)

• Desipramine (Norpramin)

• Amoxapine

• Doxepin (Silenor)

• Imipramine

• Nortriptyline (Pamelor)

Notable MAOIs include:

• Phenelzine (Nardil)

• Selegiline (Emsam, Zelapar)

• Isocarboxazid (Marplan)

• Tranylcypromine (Parnate)

These types of antidepressants can increase the risk of short-term neffy side effects. These include higher blood pressure, faster heart rate, and headaches. Anxiety, sweating, and nausea are also possible.

If you're concerned about this interaction, you might be able to switch to an antidepressant that doesn't interact with neffy. Talk to a healthcare professional if you want to make this change. SSRI and SNRI antidepressants are very common, and they aren't known to interact.

4. Some antihistamines

Certain antihistamines may also interact with neffy. Again, they can amplify the effects of neffy when combined. Increased epinephrine activity raises the risk of experiencing side effects.

Some common antihistamines that interact with neffy are chlorpheniramine (Aller-chlor) and diphenhydramine (Benadryl). These first-generation antihistamines are often found in OTC cough and cold products. And they tend to make you drowsy.

It's a good idea to monitor your blood pressure more closely if neffy and one of these antihistamines are in your system at the same time.

Keep in mind: If you think you're having an allergic reaction, you may be tempted to reach for an antihistamine. But in cases of severe allergic reaction or anaphylaxis, antihistamines aren't a substitute for epinephrine.

5. Levothyroxine

Levothyroxine (Synthroid, Unithroid, others) is a common medication for hypothyroidism. It interacts with neffy in a similar fashion. Levothyroxine may increase the effects of neffy in the body, worsening the risk of developing side effects. These include high blood pressure, palpitations, and tremors.

If you take levothyroxine every day, keep an eye out for these types of side effects after using neffy. Let your healthcare team know if they get worse or don't go away on their own.

6. Alpha blockers

Another group of medications that interact with neffy are alpha blockers. Alpha blockers include medications such as prazosin (Minipress), doxazosin (Cardura), and tamsulosin (Flomax). Alpha blockers are typically used to manage high blood pressure and benign prostatic hyperplasia (BPH).

These medications have conflicting effects. Neffy causes your blood pressure and heart rate to rise. But alpha blockers can block this effect.

It isn't necessary to completely avoid alpha blockers when using neffy. But it's important to note that alpha blockers may reduce its effectiveness. If you're having a severe allergic reaction that isn't getting better, call 911 or seek emergency medical attention right away.

7. Beta blockers

Neffy also interacts with a group of medications known as beta blockers. These are typically prescribed to treat high blood pressure and certain heart conditions.

Some beta blockers are cardioselective, meaning they work primarily in your heart. This includes medications like metoprolol (Lopressor, Toprol XL) and atenolol (Tenormin). Other beta blockers are non-selective. This means they work more broadly throughout your body. Examples of non-selective beta blockers include propranolol (Inderal) and carvedilol (Coreg).

The consequence of this interaction depends on the beta blocker you're prescribed. Non-selective beta blockers may hypothetically amplify neffy's effects on blood pressure. This could potentially lead to a meaningful blood pressure increase. In contrast, cardioselective beta blockers may cause neffy not to work as well.

Talk to your cardiologist if you take a daily beta blocker. They can help you develop an action plan for what to do if you need to administer neffy. And if you do need to use neffy, your healthcare team will likely monitor your blood pressure and heart rate closely while you're recovering from your allergic reaction.

8. Ergot alkaloids

Ergot alkaloids are an older group of medications that are sometimes used to treat migraines. They're another type of medication that can interact with neffy. Ergot alkaloids include medications like ergotamine / caffeine (Migergot) and dihydroergotamine (Migranal).

Ergot alkaloids can narrow your blood vessels. They can severely raise your blood pressure when paired with neffy. This can lead to a hypertensive emergency. They can also cancel out some neffy's critical effects on the body during a severe allergic reaction. It's usually not recommended to take ergot alkaloids with neffy.

Talk to a healthcare professional about alternative medications to treat migraine headaches. Many newer migraine medications are available that don't interact with neffy.