Allergies and Sensitivities During IV Therapy

Allergies are an important safety concern during IV therapy. Unlike oral medications, IV drugs enter your bloodstream immediately — which means allergic reactions can develop quickly. Always tell your care team about every allergy and sensitivity you have, no matter how minor it seems.

This guide explains the types of allergies relevant to IV care, what reactions look like, and what to do if you suspect a reaction.

Why Allergies Matter More with IV Medications

When you take a pill, it is absorbed slowly through the gut. If a reaction starts, you have some time to respond. With IV therapy, the medication goes directly into the bloodstream at a controlled rate — and a serious allergic reaction can begin within seconds to minutes of the infusion starting.

This is why:

Your allergy list is verified at every medication administration
Certain medications are given under close monitoring, especially the first dose
Emergency medications (epinephrine, antihistamines, steroids) are always nearby in clinical settings

Tell Your Care Team About ALL of the Following

When you arrive for care, or any time your medications change, share your complete allergy history:

Drug allergies

Any medication that has ever caused you a rash, hives, difficulty breathing, swelling, or any other reaction — including antibiotics (especially penicillin), sulfa drugs, aspirin/NSAIDs, opioid pain medications, contrast dyes, chemotherapy agents, and any others
The specific reaction you had (rash, hives, throat swelling, breathing problems, anaphylaxis)
When the reaction occurred and how it was treated

Important: There is a difference between an allergy and a side effect or intolerance. Nausea from an antibiotic is a side effect; hives or difficulty breathing are signs of an allergic reaction. Both are important to report, but they are managed differently. Tell your care team exactly what happened when you had the reaction — the detail helps them determine the risk and whether alternative medications are available.

Latex allergy

Latex is a natural rubber material found in some medical equipment — including some types of gloves, IV stoppers, some tubing components, and medical devices. Latex allergy ranges from mild skin reactions to severe anaphylaxis. This is an important allergy to disclose because:

Your team can use latex-free equipment throughout your care
An unrecognized latex allergy can cause a serious reaction during an IV procedure
Some IV bags have latex ports — latex-free alternatives exist

Tell your team: “I have a latex allergy.” If you have severe latex allergy, ask your care team to confirm that all equipment being used for your care is latex-free.

Who is at higher risk for latex allergy?

People who have had multiple surgeries, particularly as children
Healthcare workers (through occupational exposure)
People with spina bifida
People with a history of allergy to certain foods: banana, avocado, kiwi, chestnut, and passion fruit (these share proteins with latex — called latex-fruit syndrome)

Adhesive and tape sensitivities

Many vascular access devices are secured with adhesive dressings, tapes, or specially designed securement devices. Some patients have sensitive skin that reacts to the adhesive:

Contact dermatitis from tape or adhesive: redness, itching, blistering, or skin breakdown under the tape
Sensitivity to specific products (e.g., certain brands of transparent dressing or Tegaderm)

This is not the same as a systemic allergy, but it is still important. Tell your team: “I have sensitive skin” or “Tape usually causes a rash for me.” There are alternative securement options available, including silicon-based adhesives and non-adhesive securement devices.

Antiseptic sensitivities

Chlorhexidine (CHG): Chlorhexidine is the primary antiseptic used to clean your skin before IV insertion and for catheter care, including CHG bathing cloths for patients with central lines. Most people tolerate CHG without any problems, but a small number of people have CHG allergy — which can range from a skin rash to anaphylaxis.

Signs of CHG sensitivity: redness, rash, or hives developing at the site where CHG was applied, or more widespread symptoms during a CHG-based procedure.

If you have had a reaction to CHG before, tell your care team. Alternative antiseptics (povidone-iodine, alcohol) can be used.

Povidone-iodine: Some patients are sensitive to iodine-based antiseptics. Tell your team if you have ever reacted to iodine or iodine-based products (including CT contrast dye, seafood allergy is sometimes — though not always — linked to iodine sensitivity; discuss with your team if relevant).

Metal sensitivities

Implanted ports and some catheter components contain metal (typically titanium or stainless steel). True metal allergies to titanium are extremely rare. If you have a known allergy to specific metals, discuss this with your care team before an implanted port or any surgically placed device is considered.

Types of Allergic Reactions

Mild reaction

Localized redness or itching at the IV site or elsewhere
Mild rash or hives in a limited area
Runny nose, watery eyes

What to do: Tell your nurse right away. The infusion may be slowed or paused while your nurse assesses the reaction. Antihistamines may be given.

Moderate reaction

More widespread hives or rash
Flushing (face and body feeling hot and looking red)
Nausea, vomiting, or abdominal cramping
Mild wheezing or difficulty breathing
Swelling around the face or lips (not inside the throat)

What to do: Call your nurse immediately. The infusion will be stopped. Treatment with antihistamines, steroids, and possibly other medications will be started. You will be monitored closely.

Anaphylaxis (severe allergic reaction — EMERGENCY)

Anaphylaxis is a severe, life-threatening allergic reaction that can develop rapidly. This is a medical emergency. Symptoms include:

Throat tightening or swelling — difficulty swallowing, feeling like the throat is closing
Severe breathing difficulty — wheeze, stridor (a high-pitched sound when breathing in), or inability to catch breath
Sudden drop in blood pressure — lightheadedness, dizziness, feeling faint, or loss of consciousness
Rapid, weak pulse
Severe hives spreading rapidly over the body
Swelling of the tongue or lips (rapidly worsening)
Pale or bluish skin color

What to do: If you are in a clinical setting (hospital, infusion center), press your call button and shout for help — do not wait. Anaphylaxis requires immediate treatment with epinephrine (adrenaline). Staff are trained to respond to this emergency.

If you are at home and experience these symptoms, call 911 immediately. If you have a prescribed epinephrine auto-injector (EpiPen), use it and then call 911. Even if symptoms seem to be improving after epinephrine, you must still go to an emergency room, as biphasic reactions (a second wave of symptoms hours later) can occur.

Recognizing a Reaction During an Infusion

Reactions can start at any time during an infusion but are most likely to occur:

In the first 15–30 minutes of a new medication’s first dose
After a dosage increase
If there has been a break in treatment and it has been restarted

During any infusion, tell your nurse immediately if you notice:

Any new itching, rash, or hives
Flushing or feeling suddenly very warm
Difficulty breathing or unusual shortness of breath
Tight feeling in the chest or throat
Nausea that comes on suddenly
Dizziness, lightheadedness, or feeling faint
Headache that comes on suddenly
Any symptom that seems new or unusual for you

Never assume a reaction will pass on its own. Early identification means earlier treatment, which is much safer.

Allergy Cross-Reactivity

Some patients are told they are allergic to one drug and wonder if they can safely receive a related drug. This is called cross-reactivity. Examples:

Penicillin and cephalosporins: There is a historical concern about cross-reactivity between penicillin antibiotics and cephalosporins (another class of antibiotics). Modern evidence suggests cross-reactivity is actually quite low, but your care team will review your specific history before using either class.
Sulfa antibiotics and other sulfa drugs: Some patients allergic to sulfa antibiotics are cautioned about other drugs with sulfa-containing groups — though the relationship is complex and not always clinically significant.

If you are unsure whether a medication you are being offered might be related to something you reacted to before, ask. The pharmacist is an excellent resource for these questions.

After a Reaction: What Happens Next

If you have a reaction, your care team will:

Stop or adjust the infusion
Treat the reaction with appropriate medications
Document the reaction in your medical record and update your allergy list
Work with the prescribing physician to identify a safe alternative medication if needed
Inform you of what was documented and what it means for future care

Make sure the reaction is documented. Before leaving any care setting where you had an allergic reaction, confirm:

The specific medication that caused the reaction has been added to your allergy record
The type of reaction (rash, hives, anaphylaxis) is documented
You understand what this means for future medication choices

Carry information about your allergies with you — in your wallet, on your phone, or on a medical alert bracelet for severe allergies.

Latex-Safe Care: What to Expect

If you have a latex allergy, tell every care team member at every encounter — do not assume the information has been passed on. Proactive advocacy matters:

Ask: “Is this equipment latex-free?”
In a hospital: request that “latex allergy” be clearly visible on your wristband and at the head of your bed
If you are going to a procedure room or OR: notify the procedural team directly before the procedure begins
If you are allergic to latex, you may also react to latex-containing balloons, rubber bands, and rubber gloves used by other people nearby — latex proteins can become airborne. Alert your care team if you are very sensitive.

This guide is for educational purposes and is not a substitute for advice from your own healthcare team. If you have concerns about specific allergies, discuss them with your physician, nurse, or pharmacist.