Nasal decongestants are useful medications for the common cold and for allergic rhinitis with congestion. They are safe for most patients, but their labeling includes a host of precautions. Failure to follow the label can increase the risk of adverse reactions in users. It is vital for pharmacists to consult with patients about these powerful pharmacological medications. Pharmacists must also be aware of the abuse of these products. Nasal decongestants include the oral decongestant pseudoephedrine (e.g., Sudafed), as well as topical sprays (e.g., Afrin, Neo-Synephrine) and inhalers (e.g., Benzedrex). It should be noted that this column does not address prescription products such as steroidal sprays (e.g., Rhinocort, Flonase). These products have their own set of adverse reactions.
Both oral and topical nasal decongestants are contraindicated for patients with heart disease (they increase the workload of the heart), hypertension (they raise blood pressure), thyroid disease (they increase the risk of adverse reactions), diabetes, or, in men, difficulty in urination caused by an enlarged prostate. These problems are more common with oral pseudoephedrine than with topical sprays, since properly administered nasal sprays remain in the nasal mucosa.
All nasal decongestants are contraindicated in pregnancy without a physician recommendation. For instance, a 32-year-old in her 35th week of pregnancy consulted with a physician for inability to breathe. She had developed nasal congestion common to pregnancy and began self-medicating with nonprescription nasal decongestants. She obtained relief for a short period and was able to sleep but noticed that her periods of relief had become shorter. In response, she increased use of the products to constant levels, even though they had entirely ceased to show any benefit. This phenomenon, discussed below, is known as rhinitis medicamentosa (RM). At the time she was seen, she admitted that her congestion was so severe that she had contemplated terminating her pregnancy. Physician-ordered beclomethasone spray, increased household humidification, and nasal strips were required to wean her from the decongestants. Thus, all pregnant patients who have nasal congestion should be immediately referred to a physician.
Other dangers of using pseudoephedrine in pregnancy include vasoconstriction of the uterine arteries, which reduces fetal blood supply. This may cause the link between pseudoephedrine use in the first trimester and the development of gastroschisis.[2,3] In this anomaly, a fissure develops in the fetus' abdomen, perhaps allowing protrusion of the intestines.
While decongestants share many adverse reactions (e.g., insomnia, tachycardia), a great deal of attention has been given to their possible role in stroke. When proof of this link accumulated, FDA asked manufacturers to cease marketing of phenylpropanolamine, the chief suspect in many incidents. Plaintiffs throughout the country are pursuing legal actions.
Long-term use of topical nasal decongestants can cause RM. Patients can avoid other long-term effects by following dosing instructions on the label of OTC products. However, long-term use of oral decongestants containing pseudoephedrine could lead to seizures, hallucinations, pallor, headache, or insomnia.
All labels for pseudoephedrine products must state: "Do not take this product if you are now taking a prescription monoamine oxidase inhibitor (MAOI) (certain drugs for depression, psychiatric or emotional conditions, or Parkinson's disease), or for two weeks after stopping the MAOI drug." At this time, the only MAOI medications marketed are Nardil and Parnate. If MAOIs are taken with decongestants, the patient may experience a life-threatening rise in blood pressure.
In an early paper discussing RM, authors described the case of a patient who was so severely addicted to nose drops that medical personnel were forced to remove numerous bottles from her belongings without her knowledge during a hospitalization for the addiction.
RM is an occasional adverse effect caused by use of topical nasal decongestants. The typical patient is one with a minor case of nasal congestion, perhaps as a result of the common cold. The patient purchases any one of several topical nasal decongestants, obtaining relief from its use. However, the patient notices that when the decongestant effect subsides, nasal congestion is worse than it originally was. The patient who reuses the decongestant may find that doses must be increased and intervals between use must be shortened. Thus, the patient displays the classic phenomenon of medication tolerance, in which larger and larger doses of an abused substance are necessary to achieve the same effect as the initial dose.
Recent attention has focused on the role of preservatives in topical nasal products, especially benzalkonium chloride, a preservative found in formulations of oxymetazoline.[8,10,11,12] In a 1995 study, investigators randomized 20 healthy volunteers without nasal congestion to receive oxymetazoline nasal spray, either with or without benzalkonium chloride. Volunteers used the products three times daily for 30 days. Both groups exhibited rebound swelling and nasal stuffiness, but those taking the spray containing benzalkonium chloride had significantly worse symptoms. Later research suggested that shorter use times may increase the safety factor, but the authors still counseled against exceeding the labeled period.
Treatment of RM is immediate withdrawal, with possible use of steroid nasal spray, perhaps combined with oral corticosteroids, systemic decongestants, and/or antihistamines.[14,15,16] Some patients respond only with nocturnal sedation, steroid injection into the inferior nasal turbinate, and/or surgery.
Despite awareness of the abuse potential of these products, pharmacists began to see an unprecedented wave of abusers in the late 1990s. Unfortunately, there was a growing demand for methamphetamine across the country. In the past, the preferred starter chemical had been ephedrine, but federal efforts to stem the tide of meth abuse had reduced its availability. Since pseudoephedrine was largely uncontrolled, it became the preferred starter chemical for thousands of meth labs.
While meth labs blanket the United States, it seems that the central states lead in numbers of labs. Missouri was the number 1 state in 2003, but Arkansas, Kansas, Texas, and Oklahoma were also hard hit. The number of meth labs in Oklahoma rose by 12,000% in the past decade. This may be due to a favorable geography, the number of interstate highways in the region, and the Midwest's equal distance to major markets on the coasts.
Pharmacies are frequent sources of meth lab chemicals. Federal and state laws may give the pharmacist some help in battling this menace. In 1996, Congress passed the Comprehensive Methamphetamine Control Act, which allowed consumers to purchase 24 grams of pseudoephedrine per transaction from retailers. Purchasers could buy as many as 40 boxes containing 24 tablets each, far too much for legitimate use. In 2000, Congress passed the Methamphetamine Anti- Proliferation Act, which further reduced the allowable sale to 9 grams, which is 366 tablets of 30 mg pseudoephedrine HCl (about 16 boxes of 24 tablets). Because this is still an excessive amount for legitimate use, some pharmacies have voluntarily limited pseudoephedrine sales. Some stores also keep it behind the register, creating a third class of drugs.
Pharmacists should ask proposed pseudoephedrine buyers about the extent of nasal congestion and accompanying symptoms to ensure that sales are valid. They should ask about the duration of nasal congestion. If it is in excess of one week, the "patient" should be denied the product since a physician referral is indicated.
Other purchases the meth lab requires (e.g., coffee filters, lithium batteries, drain cleaner, table salt, rubbing alcohol, and red phosphorus from matches) may tip the pharmacist to illegal use. Those suspected of running meth labs should be reported to the local authorities. In Oklahoma, anyone found in possession of three meth precursors can be charged with attempting to manufacture meth.
US Pharmacist. 2004;29(7) © 2004 Jobson Publishing
Cite this: Safe Use of Nasal Decongestants - Medscape - Jul 15, 2004.