Cold Medications
There is very little information on over-the-counter (OTC) cold medications during pregnancy, as very few studies have been published. However, current available evidence suggests most OTC cold medications are likely safe with proper and limited short-term use.
It is often recommended that pregnant women avoid several of these medications during the first trimester, but this is largely based on caution due to a lack of information. Any future research could change the safety profile of any of the below described medications.
Before using any OTC medication, it is very important pregnant women talk to their HCP and read the label carefully for active ingredients, side effects, appropriate dosing, and warnings.
Many cold medications have more than one active ingredient, all of which act differently within the body. Pregnant women should aim to use medications with as few ingredients as possible, based only on their current symptoms and call their HCP with any questions.
Background
The management of a common cold and its related symptoms (cough, nasal stuffiness, sneezing, runny nose, fever and sore throat) during pregnancy may require a risks and benefits discussion with an HCP. Many symptoms resolve on their own within 7 to 10 days, and there is a significant lack of safety data regarding over-the-counter (OTC) cold medications during pregnancy.
Before taking any OTC medication for cold symptoms, pregnant women should:
Talk to their HCP first
Be aware of the purpose (indications) of each different type of medication
Make note of the proper dosing and time between doses
Be familiar with each individual ingredient (some could have three or more)
Take only the medications needed for specific symptoms
Be aware of possible side effects
Be aware of taking too much acetaminophen
Be aware of alcohol content
Although these medications are readily available, pregnant woman should always call or talk to their HCP about their symptoms first, especially with a fever. HCPs may want to screen for influenza, COVID-19, RSV, strep throat, or rule out other potential causes, which could require a more specific treatment plan.
Note: The previous drug classification system used by the United States (U.S.) Food and Drug Administration (FDA) that utilized categorical letters (A, B, C, D, and X) for medications during pregnancy was deemed misleading and was replaced in 2015. Therefore, this site does not refer to these prior letter categories, because their continued use causes further confusion. Read more.
Vitamin C
The ability for vitamin C to fight a common cold has not been backed by evidence since the original publication came out in the 1970s. While there is some evidence in small studies that vitamin C taken at the start of a cold might ease symptoms, large doses do not help cure or prevent colds.
It has been recommended that pregnant women obtain a daily requirement of 85 milligrams (mg)/day of vitamin C, compared with 75 mg/day before pregnancy, but as high as 400 mg/day has also been recommended.
When taken at appropriate doses, oral vitamin C supplements are generally considered safe. Supplements usually contain vitamin C in the form of “ascorbic acid”. Vitamin C is water-soluble, and thus any amount in excess will exit a pregnant woman’s body through urine.
However, large amounts (more than 1,000 mg per day) of vitamin C can cause stomach pain, nausea, vomiting, diarrhea, heartburn, fatigue, headache, insomnia, kidney stones, and/or skin flushing.
Read more detailed information regarding vitamin C and pregnancy.
Zinc Lozenges
Brand names: Cold-Eeze® and Zicam® (two of the most common)
Interest in zinc lozenges for treating the common cold first arose in 1983, when the cold symptoms of a 3‐year‐old girl with leukemia disappeared soon after she dissolved a therapeutic zinc tablet in her mouth instead of swallowing it.
It was assessed the slow dissolve of the tablet in her mouth may have had local effects on the mouth and throat region. This led the girl's father, who was a physician, to conduct the first randomized placebo‐controlled trial on the effects of zinc lozenges on common colds. In that study, zinc gluconate lozenges were shown to significantly shorten the duration of cold symptoms.
However, a series of trials on zinc lozenges have been carried out since then with variable results. These inconsistencies are likely due to the seven-fold variation in daily dosing (up to 200 mg/day in some studies), type of lozenge, and type of respiratory infection observed among the trials.
Further, other reviews on zinc and the common cold have been published but some of them had methodological problems and were withdrawn.
While it is possible that zinc could shorten the duration of cold symptoms, high zinc supplementation, even short-term, has not been studied during pregnancy, and the recommended daily amount of zinc during pregnancy is 11 to 12 mg/day. Further, while the tolerable upper intake level of zinc for all adults is recommended at 40 mg/day, it is possible that amounts up to 80 mg/day may be needed to see any effect on the reduction of cold symptoms.
Of additional consideration is that even in non-pregnant individuals, the optimal composition of zinc lozenges, dosing, and timing is not known, requires further research, and not all zinc preparations are expected to have the same effect on cold symptoms.
Note: Some individuals have permanently lost their sense of smell due to the use of zinc-containing nasal gels or sprays. In June 2009, the FDA warned consumers to stop using three zinc-containing intranasal products because they might cause anosmia (loss of smell), which have since been recalled.
Pregnant women should talk to their HCP prior to taking OTC medications or lozenges containing zinc (read more detailed information on zinc during pregnancy).
Throat Lozenges/Spray (Anesthetics)
Brand Names: Chloraseptic® tablets/lozenges*, Hurricaine®, Americaine®, Sucrets®, Cepacol®, Vicks®, Ricola®
*Chloraseptic® spray (vs. tablets) contains phenol, not benzocaine
Sprays or lozenges that contain local anesthetics are indicated to help numb the throat to temporarily relieve soreness. Ingredients include benzocaine, lidocaine, phenol, menthol, and dyclonine (women should always check the label).
There is no safety evidence regarding the use of most throat sprays and lozenges during pregnancy. However, in at least one study that was published, the use of Kalgaron® (lidocaine) or Strepsils® (antiseptic) lozenges during pregnancy were not associated with an increased risk of birth defects, miscarriage, or decreased birth weight.
Benzocaine has not been well-studied during pregnancy, but is currently assessed to have a low absorption rate, similar to other topical medications. Therefore, it is not expected to harm a fetus during pregnancy when used appropriately.
Note: According to the FDA, while benzocaine is safe to use in limited doses, it can cause a condition known as methemoglobinemia, in which the amount of oxygen carried through the blood is greatly reduced. In May 2018, the FDA required manufacturers to add a warning to the label, add contraindications, and direct parents and caregivers not to use the product for teething, and not to use in infants and children younger than 2 years of age. There were no specific contraindications for pregnant women.
Dextromethorphan (Suppressant)
Brand Names: Robitussin®, Delsym® (“DM”)
Coughing, and the mechanisms by which viruses cause coughing are still not understood, and there are no effective cough medications that can cure a viral-induced cough. Further, no leading singular ingredient has been deemed most effective against cough, including prescription preparations. However, OTC cough suppressants can offer some symptom relief.
Dextromethorphan (DM) is a cough suppressant used in OTC medications to reduce coughing. It works on the brain to suppress the signals that trigger the cough reflex. Women should always check the label of OTC cough medications, as most usually contain additional ingredients such as acetaminophen or antihistamines.
Of the limited studies conducted specifically on DM and pregnancy, no associations were found between the drug and an increased risk of birth defects, but studies were small. Concerns have been raised due to neural tube and cardiac defects found in animal studies, but these findings have not been found in humans, mostly due to dosage used and other factors.
For most of the population, DM metabolizes quickly, and only about 1% to 2% enters an individual’s circulation; however, absorption rate is highly dependent upon an individual's ability to metabolize medications, which is highly variable.
Additionally, women’s metabolisms during pregnancy change even more dramatically, mostly due to an increase in blood volume and gastric motility. This is one of the major components of the importance of studying medications during pregnancy, as dosing is likely significantly affected. This makes it very hard to study the effect of cough syrup (or any medication) on pregnancy outcomes.
Guaifenesin (Expectorant)
Brand Names: Mucinex®
Guaifenesin is an expectorant medication taken to assist in “bringing up” (expectorating) phlegm/mucus from the airways. It has anticonvulsive, muscle relaxant, and anti-coagulant properties.
Guaifenesin is available in immediate-release or extended-release formulations. The maximum dose recommended for adults is 2,400 mg in 24 hours. Data regarding its effects on pregnancy outcomes is scarce; however, in the several studies that have been completed, no increased risk of major malformations was identified.
However, based on its anti-coagulant properties, there have been concerns that the use of guaifenesin could cause an increased risk of bleeding in the mother or fetus, possibly similar to aspirin, depending on the dose. One study found numerous birth defects and “bleeding spots” in rat fetuses, but doses well beyond human consumption were used, and the authors noted that studies using lesser doses were necessary.
Some researchers have suggested since very little is known regarding guaifenesin, although it may be safe in short-term and limited use, women should be cautious and avoid its use in the first trimester. Further, the effects of guaifenesin may be compounded when other cold medications are used in the same preparation.
Pseudoephedrine/Phenylephrine (Oral Decongestants)
Brand Names: Sudafed® (may also be included in various Vicks®, Theraflu®, and Robitussin® preparations, as well as generic brands; women should always check the label)
Pseudoephedrine and phenylephrine are the most common nasal decongestants (taken orally) in OTC cold medications. These medications work by constricting blood vessels. Based on this mechanism of action, they are also used to treat low blood pressure and hemorrhoids.
Vasoconstrictor: a medication that constricts or narrows blood vessels, which improves circulation (and swelling) and relieves nasal congestion; it also may increase blood pressure and redirect blood flow. Pseudoephedrine releases the body’s stores of norepinephrine/noradrenaline, which naturally constricts blood vessels.
The concern for the use of these medications during pregnancy is that by elevating blood pressure or causing vasoconstriction, this could affect uterine arteries as well, thereby restricting blood and oxygen from the fetus.
However, it is unclear if the amount used by pregnant women (in appropriate doses) would be enough to cause complications, and this has not been studied in humans. Further, several cohort and case-control studies have failed to show any increased risk of malformations when oral decongestants were used during pregnancy.
Although more research is necessary, based on the possibility these medications could affect blood flow to the uterus, some researchers have advised against their use in women trying to get pregnant, who are in the first trimester, and during labor.
Pseudoephedrine can cause (rare) side effects such as:
Nervousness
Restlessness
Trouble sleeping
Difficult or painful urination
Dizziness or light-headedness
Fast or pounding heartbeat
Headache
Increased sweating
Nausea or vomiting
Trembling
Unusual paleness
Weakness
Note: Pseudoephedrine is used in the manufacturing of methamphetamine, and therefore is tightly controlled at pharmacies and grocery stores.
Diphenhydramine/Chlorpheniramine (Antihistamines)
Brand Names: Benadryl®, Allergy Relief®
Anthistamines have good safety profiles during pregnancy, and are often used in the first-trimester for nausea and vomiting of pregnancy (NVP) relief. Read more on antihistamine safety during pregnancy (as studied for NVP).
Acetaminophen (Analgesic)
Brand Names: Tylenol®, Paracetamol®
Acetaminophen is a common ingredient in many OTC cold medications. Women need to make sure they read the labels of all medications; exposure to high doses of acetaminophen can occur quickly with combination medications, and caution is warranted regarding its indiscriminate use during pregnancy. Read more detailed information regarding acetaminophen and pregnancy.
Oxymetazoline/Xylometazoline (Decongestant Spray)
Brand names: Afrin®
Xylometazoline and oxymetazoline are OTC inhaled decongestant sprays that constrict (shrink) blood vessels in the nose, relieving congestion.
The extent of systemic absorption and whether either drug crosses the placenta is not known, and the same concerns exist regarding possible blood vessel constriction, albeit likely to a much lesser degree than pseudoephedrine/phenylephrine.
Therefore, it is still often recommended that nasal decongestant spray always be used at the lowest possible dose, preferably after the first trimester, and for no longer than 2 or 3 days due to possible rebound effects, which makes congestion worse.
More specifically, these products should be used only once every 10 to 12 hours, and no more than twice in a 24-hour period. As these medications provide immediate, but temporary relief, it is easy for women to overuse them.
Rhinitis medicamentosa is the term used for nasal congestion caused by extended use of these drugs. Drug-induced nasal congestion can occur as soon as three days of use, even if used only at bedtime. Congestion will continue to get worse until these medications are stopped for several days.
Note: For pregnant women experiencing gestational rhinitis, which is nasal congestion due to pregnancy-related blood volume changes and not an illness, nasal decongestant spray is not recommended. Gestational rhinitis can last for weeks, even months, and these sprays should not be used for more than 2 to 3 days (read more on nasal congestion during pregnancy, to include lifestyle modifications that may relieve congestion).
Action
There is very little safety data regarding OTC cold medication active ingredients during pregnancy. Therefore, women should talk to their HCP prior to the use of any OTC medication.
Women should read the label carefully for active ingredients, side effects, appropriate dosing, and warnings before taking any medication. Many cold medications have more than one active ingredient, all of which act differently within the body. Pregnant women should aim to use medications with as few ingredients as possible, based only on their current symptoms and call their HCP with any questions.
Resources
Treating the common cold during pregnancy (Can Fam Physician. 2008)
Drugs and Lactation Database (LactMed) (U.S. National Library of Medicine)