Pseudoephedrine sulfate

What it is

Pseudoephedrine sulfate is the sulfate salt of pseudoephedrine, a stimulant amine closely related to ephedrine. In US over-the-counter medicines the sulfate salt appears almost entirely inside extended-release combination tablets, where the Drug Facts panel lists it as the nasal decongestant alongside an antihistamine. It is a water-loving (hydrophilic) compound, which is why formulators have to work to separate it from the fat-loving antihistamines it is paired with. The same molecule occurs naturally as an alkaloid in Ephedra plants.

What the research says

The evidence for pseudoephedrine is real but modest. Cochrane's review of decongestants used on their own found that repeated doses gave a small improvement in how blocked people said their nose felt, on low-quality evidence, and the reviewers said the clinical relevance of that small effect is unknown. Paired with an antihistamine it performs better on overall recovery from a cold. It measurably opens the nose on instrument testing. It also raises blood pressure and heart rate slightly, more so at higher doses and with immediate-release products, and it has been linked in case reports to ischaemic colitis. At the doses used for congestion it does not improve athletic performance.

Evidence grade: Limited evidence.

How it works

Drug class: Indirect-acting sympathomimetic amine, used as an oral nasal decongestant

Pseudoephedrine appears to work indirectly rather than by switching on blood-vessel receptors itself. In isolated mouse and human atrial muscle it behaved as an indirect sympathomimetic, releasing stored noradrenaline: the contractile effect was attenuated by cocaine, which blocks the reuptake of noradrenaline into nerve endings, and antagonised by propranolol, which blocks the beta receptors the released noradrenaline then acts on. That was heart tissue in a laboratory bath. The same released-noradrenaline mechanism is what is thought to narrow blood vessels in the nose and so reduce the swelling of its lining, and what explains the small rises in blood pressure and heart rate measured in human trials, but this study tested neither the nose nor blood vessels. (Source 1)

What it is used for

• Repeated doses gave a small improvement in self-rated congestion on low-quality evidence, and Cochrane says the clinical relevance of that small effect is unknown. Evidence: limited. (Source 2)
• The combination-tablet evidence is indirect. A single loratadine-pseudoephedrine tablet opened the nose more than placebo or a fluticasone spray on airflow measurement after ragweed challenge. The Cochrane review that found a benefit on global recovery was in the common cold rather than hay fever, and it pooled antihistamine-decongestant combinations generically without isolating pseudoephedrine. Evidence: limited. (Source 3)
• A 2026 meta-analysis of three randomised trials from 1992 to 1998 found a clear reduction in barotrauma, but the authors call the evidence dated and too small to detect rare harms. Evidence: limited. (Source 4)
• No trial in either review improved performance at the doses used for congestion. The 2015 systematic review classed 60 to 120 mg as therapeutic and found no ergogenic effect there, with clinically significant results only at 180 mg or more, while saying it could draw no firm conclusions overall. The 2018 meta-analysis split its trials at 170 mg and found effects on time-trial and heart-rate measures only above that. Pseudoephedrine is banned in sport by the World Anti-Doping Agency, with an analytical urinary threshold of 150 mcg/mL. Evidence: not-supported. (Source 5)

Interactions

• Monoamine oxidase inhibitors (MAOIs), including certain antidepressant, psychiatric and Parkinson's disease medicines (label): The US label treats this as an absolute contraindication rather than a caution, and extends it for two weeks after the MAOI is stopped. (Source 6)
• Treated high blood pressure and the medicines used for it (clinical trial): Pooled trial data show the blood-pressure rise in people whose hypertension is already controlled is about the same small size as in everyone else, around 1 mm Hg systolic. That is small, but it is a rise rather than nothing, and the label tells people with high blood pressure to ask a doctor first. (Source 7)
• Caffeine (clinical trial): The trial literature we found compares the two rather than testing them together. In a crossover trial in trained cyclists, 200 mg of caffeine and 180 mg of pseudoephedrine did not differ significantly in overall time-trial time, and caffeine was faster over the second half. No trial of the two taken together was found. (Source 8)
• Alcohol, taken with caffeine and stimulant Ephedra alkaloids (case reports): The only human report we found that links alcohol to this family of compounds concerns Ephedra alkaloid tablets, not a pseudoephedrine medicine. A man developed short-lived acute psychosis after alcohol, caffeine and Ephedra alkaloid tablets; his urine contained ephedrine and pseudoephedrine. The authors read the episode as an interaction. This is one case report about a herbal product, not evidence about an over-the-counter decongestant taken with a drink. (Source 9)
• Bitter orange extract and p-synephrine, sold in weight-loss and pre-workout supplements (theoretical): p-Synephrine is a sympathomimetic in the same family. Pooled placebo-controlled trials show prolonged use raises both systolic and diastolic blood pressure, so taking it alongside a decongestant that also raises blood pressure is a plausible additive risk. No trial has tested the pair together, so this is reasoning from the separate effects, not a measured interaction. (Source 10)

Stopping it

• Nothing in the literature we searched describes a withdrawal syndrome or a taper for oral pseudoephedrine, and no rebound congestion is described for the oral route as it is for decongestant nasal sprays. What the US label sets is a time limit on continuing: it directs people to stop and ask a doctor if symptoms have not improved within 7 days. (Source 6)
• Where stopping clearly mattered was in the ischaemic colitis cases: all four women recovered after stopping pseudoephedrine with supportive care, and none relapsed over 8 to 12 months off it. (Source 11)
• Misuse rather than ordinary use is where the serious toxicity appears, and what was reported is psychosis, not dependence. A single-author case report describes acute psychosis with hallucinations in an 18-year-old after he injected 60 mg of pseudoephedrine into a vein, and the author reviewed other reported cases of psychosis. Nothing in that report describes tolerance, craving or withdrawal. (Source 12)

What goes wrong

A decongestant combined with an analgesic caused significantly more adverse effects than the control, on high-certainty evidence. (Source 13)

• Systematic review, High certainty.
• Size: 7 trials, 2,575 participants; adverse effects from 1,122 active versus 675 control participants.
• Who: adults and children with the common cold.
• How long: 3 to 10 days.
• Result: 199/1122 versus 75/675; OR 1.62 (95% CI 1.18 to 2.23); number needed to treat for an additional harmful outcome 17.
• Funding: independent (Cochrane review)

Limit of this finding: The figures in this sentence do not quite recompute from one another and the review prints them as they stand: 199 out of 1122 is 17.7% and 75 out of 675 is 11.1%, which gives an odds ratio nearer 1.72 than the printed 1.62, and about one extra person harmed for every 15 treated rather than every 17. The direction is not in doubt, because the interval 1.18 to 2.23 excludes 1, but treat the exact numbers as approximate.

Adverse effects: the decongestant-analgesic group experienced significantly more adverse effects than the control group (199/1122 versus 75/675; OR 1.62 95% CI 1.18 to 2.23; high certainty evidence; number needed to treat for an additional harmful outcome (NNTH 17).

Pooled trial data show oral pseudoephedrine raises systolic blood pressure and heart rate by a small but statistically significant amount, including in people whose hypertension is controlled. (Source 7)

• Meta-analysis, Moderate certainty.
• Size: 1,285 patients across 24 trials with extractable vital signs (45 treatment arms)
• Who: adults, including a subgroup with controlled hypertension.
• How long: varied; shorter duration of use was associated with greater systolic rises.
• Result: SBP +0.99 mm Hg (95% CI 0.08 to 1.90); HR +2.83 beats/min (95% CI 2.0 to 3.6); DBP +0.63 mm Hg (95% CI -0.10 to 1.35, not significant); controlled hypertension SBP +1.20 mm Hg (95% CI 0.56 to 1.84)
• Funding: not stated.

Pseudoephedrine caused a small but significant increase in SBP (0.99, mm Hg; 95% CI, 0.08 to 1.90) and HR (2.83 beats/min; 95% CI, 2.0 to 3.6), with no effect on DBP (0.63 mm Hg, 95% CI, -0.10 to 1.35). The effect in patients with controlled hypertension demonstrated an SBP increase of similar magnitude (1.20 mm Hg; 95% CI, 0.56 to 1.84 mm Hg). Higher doses and immediate-release preparations were associated with greater BP increases.

Four women developed ischaemic colitis of the splenic flexure while taking pseudoephedrine-containing medicines, and all settled after stopping it. (Source 14)

• Case series, Very low certainty.
• Size: 4 women aged 37 to 50.
• Who: three had used a pseudoephedrine medicine daily for about a week; one had used it for 6 months.
• How long: followed 8 to 12 months after stopping.
• Result: all four had colitis on colonoscopy affecting mainly the splenic flexure watershed area, with biopsies consistent with ischaemic injury; none relapsed after stopping.
• Funding: not stated.

On colonoscopy, all four patients had colitis, primarily affecting the splenic flexure in the anatomical watershed area. Other causes of segmental colitis, including infectious colitides, pseudomembranous colitis, and Crohn's disease, were not evident. Colonoscopic biopsies were consistent with ischemic injury.

Acute psychosis with hallucinations was reported after intravenous misuse of pseudoephedrine. (Source 12)

• Case report, Very low certainty.
• Size: 1 patient.
• Who: an 18-year-old male who injected pseudoephedrine hydrochloride.
• How long: single episode.
• Result: florid visual and tactile hallucinations after intravenous misuse of 60 mg; this is not an oral therapeutic exposure.
• Funding: not stated.

A case is reported of acute psychosis, including florid visual and tactile hallucinations, in an 18-year-old male after intravenous misuse of 60 mg of pseudoephedrine hydrochloride.

A 2024 pharmacology review reported that pseudoephedrine may carry a higher rate of uncommon but potentially life-threatening adverse effects than the antihistamine it was compared with. (Source 15)

• Expert review, not systematic, Low certainty.
• Size: not stated; the review drew on MEDLINE, Scopus, Embase, Google Scholar and the EudraVigilance database.
• Who: people using over-the-counter cold medicines.
• How long: not applicable.
• Result: no pooled rate, count or denominator appears anywhere in the abstract; the review states only that pseudoephedrine may induce a higher incidence of less common but potentially life-threatening adverse effects than chlorphenamine.
• Funding: not stated.

Pharmacovigilance data and case report reviews showed that pseudoephedrine may induce a higher incidence of less common but potentially life-threatening adverse effects compared to chlorphenamine. We concluded that antihistamine drugs exhibit a more favorable benefit/risk profile than vasoconstrictors for treating symptomatic common colds.

In isolated human atrial muscle, pseudoephedrine increased contraction force, apparently by releasing stored noradrenaline rather than acting on receptors directly. (Source 1)

• Lab study in cells, Very low certainty.
• Size: human right atrial preparations and mouse atrial preparations; the abstract gives n = 5 only for the amphetamine mouse result and states no n for the other arms or for the human tissue.
• Who: surgically obtained human atrial tissue and mouse atrial tissue.
• How long: acute laboratory exposure.
• Result: pseudoephedrine raised force of contraction in human atrial preparations to a mean of 287% (SEM 60%); the effect was attenuated by cocaine and antagonised by propranolol; this is tissue, not a human outcome.
• Funding: not stated.

not only amphetamine (to a mean ± SEM of 208% ± 32%) but also pseudoephedrine (to a mean ± SEM of 287% ± 60%), cathine (to a mean ± SEM of 234% ± 52%), and cathinone (to a mean ± SEM of 217% ± 65%) increased force of contraction without the need of phosphodiesterase inhibition. The contractile effects in HAP were attenuated by 10 µM cocaine and antagonized by 10 µM propranolol. We conclude that amphetamine, pseudoephedrine, cathine, and cathinone act probably via release of noradrenaline from cardiac stores as indirect sympathomimetic agents in mouse and more pronounced in human atrial preparations.

Pseudoephedrine in urine commonly makes amphetamine screening immunoassays read positive when no amphetamine-type drug is present. (Source 16)

• Survey study, Moderate certainty.
• Size: approximately 27,400 urine samples; 1,104 presumptive positives on one assay.
• Who: randomly collected human urine samples from US Navy and Marine Corps members.
• How long: not applicable; a single screening-method comparison with mass-spectrometry confirmation.
• Result: the DRI amphetamine assay flagged 1,104 presumptive positives of which only 1.99% confirmed as amphetamine, methamphetamine, MDA or MDMA; ephedrine, pseudoephedrine or phenylpropanolamine was confirmed in 833 of the 1,104 that did not confirm, and every one of those 833 contained pseudoephedrine; pseudoephedrine was present in about 3% of all samples screened, and the authors say cross-reactivity is greater than the reagent manufacturer reports.
• Funding: not stated.

The presence of EPH, PSEPH, or PPA was confirmed in 833 of the 1,104 samples that failed to confirm positive for AMP, MTH, MDA, or MDMA; all of the 833 samples contained PSEPH.

What the evidence supports

Multiple doses of a nasal decongestant gave a small improvement in self-rated nasal congestion in adults with a cold, on low-quality evidence. (Source 2)

• Systematic review, Low certainty.
• Size: 1,838 participants across 15 trials; the multi-dose congestion pooling rested on only 2 trials.
• Who: adults with the common cold; 14 of the 15 trials were adults only.
• How long: single dose to 10 days; congestion measured about three hours after the last dose.
• Result: SMD 0.49 (95% CI 0.07 to 0.92; P = 0.02), which the review itself calls a small clinical effect; GRADE low-quality.
• Funding: independent (Cochrane review)

Subjective measures of congestion were significantly better for the treatment group compared with placebo approximately three hours after the last dose (SMD 0.49, 95% confidence interval (CI) 0.07 to 0.92; P = 0.02; GRADE: low-quality evidence).

An antihistamine plus a decongestant beat placebo on global recovery from a cold, with about 4 people needing treatment for one extra person to benefit. (Source 3)

• Systematic review, Moderate certainty.
• Size: 14 trials, 1,298 participants; 6 trials (281 active, 284 placebo) pooled.
• Who: adults and older children with the common cold.
• How long: final evaluation day at 3 to 10 days.
• Result: OR of treatment failure 0.31 (95% CI 0.20 to 0.48); NNTB 3.9 (95% CI 3.03 to 5.2); 70% favourable on active treatment versus 55% on placebo.
• Funding: independent (Cochrane review)

Limit of this finding: Two things in the passage this finding comes from are the review’s own errors, not ours. In its adverse-effect sentence it prints "100/423 (13%)", but 100 out of 423 is about 24%. And it says the antihistamine-decongestant group had more adverse effects while giving an odds ratio of 1.58 with a 95% confidence interval of 0.78 to 3.21, which includes 1 — so that comparison does not actually show a difference in harm. The recovery figures quoted here are separate and their interval, 0.20 to 0.48, does exclude 1.

The odds ratio (OR) of treatment failure was 0.31 (95% confidence interval (CI) 0.20 to 0.48; moderate certainty evidence); number needed to treat for an additional beneficial outcome (NNTB) 3.9 (95% CI 3.03 to 5.2). On the final evaluation day (follow-up: 3 to 10 days), 55% of participants in the placebo group had a favourable response compared to 70% on active treatment.

Oral pseudoephedrine reduced otic barotrauma compared with placebo in a pooled analysis of three old randomised trials. (Source 4)

• Meta-analysis, Low certainty.
• Size: 490 participants across 4 double-blind randomised trials conducted 1992 to 1998; pseudoephedrine contributed 3 trials.
• Who: adults exposed to environmental pressure change.
• How long: short-term prophylaxis around a single pressure exposure.
• Result: RR 0.55 (95% CI 0.48 to 0.66; P <0.00001; I squared = 1%), with reductions in ear pain (RR 0.51), blockage (RR 0.50) and hearing loss (RR 0.49)
• Funding: not stated.

Pseudoephedrine (3 trials) significantly reduced the risk of otic barotrauma versus placebo (RR: 0.55; 95% CI: 0.48-0.66; P <0.00001; I ²=1%), and produced consistent reductions in ear pain (RR: 0.51), blockage (RR: 0.50), and hearing loss (RR: 0.49).

A single loratadine-pseudoephedrine tablet increased measured nasal airflow more than placebo or a fluticasone nasal spray after pollen challenge. (Source 17)

• Randomized trial, Moderate certainty.
• Size: single-centre crossover trial; number of participants not stated in the abstract.
• Who: adults with documented ragweed sensitivity in an environmental exposure unit.
• How long: 4 hours after a single dose.
• Result: average peak nasal inspiratory flow change 31% with loratadine-pseudoephedrine versus 12% placebo and 15% fluticasone (P < .001); at one hour 31% versus 8.6% for fluticasone (P < .001)
• Funding: not stated.

Average change in PNIF was 31% with LP in the course of the study, significantly greater than with placebo and FP (12% and 15%, respectively; P < .001).

In laboratory testing, four extended-release pseudoephedrine sulfate formulations released the drug at the rates they were designed for, and in 20 volunteers the amount absorbed tracked that release closely. (Source 18)

• Blood level study, Moderate certainty.
• Size: 20 healthy volunteers; 12 tablets per formulation tested in vitro.
• Who: healthy adult volunteers, fasted.
• How long: single dose, sampling over 16 hours in vitro.
• Result: the authors describe the in-vitro release rate as consistent with the intended design of the four formulations; linear regression of mean percentage of dose absorbed against mean in-vitro release gave r squared > 0.99, p < 0.0001 for each formulation, which they call a Level A correlation. The paper does not claim that in-vivo absorption itself matched the intended design.
• Funding: not stated.

Inspection of the individual and mean release rate data indicated that the in-vitro release rate of pseudoephedrine sulfate was consistent with the intended design of the four extended release formulations. The in-vivo bioavailability and pharmacokinetics of these formulations were evaluated in 20 healthy volunteers under fasted conditions. Wagner-Nelson analyses of the in-vivo data revealed extended release absorption profiles for all four formulations.

What the evidence does not support

The review could not reach a conclusion on single-dose decongestants because the trials measured congestion in too many different ways to pool. (Source 19)

• Systematic review, Very low certainty.
• Size: 10 single-dose trials; 7 reported congestion scores, none reported overall well-being.
• Who: adults with the common cold.
• How long: effects tested between 15 minutes and 10 hours after one dose.
• Result: no pooled estimate was possible; 2 trials recording adverse events each found no statistical difference between treatment and placebo.
• Funding: independent (Cochrane review)

Seven of 10 studies reported subjective symptom scores for nasal congestion; none reported overall patient well-being. However, pooling was not possible due to the large diversity in the measurement and reporting of symptoms of congestion.

No trial reviewed found any performance benefit from pseudoephedrine at the doses used to treat congestion. (Source 5)

• Systematic review, Low certainty.
• Size: number of participants not stated in the abstract; randomised trials to March 2015.
• Who: healthy trained and untrained volunteers in sport-performance trials.
• How long: single-dose exercise trials.
• Result: no ergogenic effect at therapeutic doses of 60 to 120 mg; effects appeared only at supratherapeutic doses of 180 mg or more.
• Funding: not stated.

Limit of this finding: The same authors say in their Conclusions that, because of the limitations of the published studies, they were unable to make any firm conclusions about pseudoephedrine’s overall effect. Read this as an absence of any benefit in the trials reviewed, not as proof that none exists.

None of the reviewed studies showed an ergogenic effect at the therapeutic dose of the drug (60-120 mg); however, supratherapeutic doses (≥180 mg) yielded clinically significant results.

A meta-analysis of randomised crossover trials found effects of pseudoephedrine on exercise measures were trivial apart from a small rise in heart rate. (Source 20)

• Meta-analysis, Low certainty.
• Size: number of participants not stated in the abstract; randomised placebo-controlled double-blind crossover trials.
• Who: healthy male and female volunteers.
• How long: single-dose exercise bouts.
• Result: heart rate effect size 0.43 (95% CI -0.01 to 0.88); all other parameters trivial; the authors call the performance benefit marginal and likely smaller than caffeine's.
• Funding: not stated.

Across all parameters, effects were trivial with the exception of HR, which showed a small positive increase in favour of PSE ingestion

Where the evidence is mixed

The Cochrane authors state the clinical relevance of the small effect is unknown and the evidence insufficient for firm conclusions. (Source 21)

• Systematic review, Low certainty.
• Size: 15 trials, 1,838 participants.
• Who: adults and children with the common cold.
• How long: up to 10 days.
• Result: no quantitative claim; the authors describe the effect as small and of unknown clinical relevance.
• Funding: independent (Cochrane review)

For multiple doses of nasal decongestants, the current evidence suggests that these may have a small positive effect on subjective measures of nasal congestion in adults with the common cold. However, the clinical relevance of this small effect is unknown and there is insufficient good-quality evidence to draw any firm conclusions.

The authors of that barotrauma review stress the evidence base is dated and too small to detect rare harms. (Source 22)

• Systematic review, Low certainty.
• Size: 4 trials, 490 participants, conducted 1992 to 1998.
• Who: adults.
• How long: short-term.
• Result: the review calls the evidence base dated (1992 to 1998) and limited in size, and asks for contemporary, adequately powered randomised trials with standardised outcome measures.
• Funding: not stated.

The evidence base is dated (1992 to 1998) and limited in size-contemporary, adequately powered RCTs with standardized outcome measures are needed.

The authors of the 2015 sport review say the published studies were too limited for them to draw any firm conclusion about whether pseudoephedrine enhances performance at all. (Source 23)

• Systematic review, Very low certainty.
• Size: number of participants not stated in the abstract; randomised trials to March 2015.
• Who: healthy volunteers in sport-performance trials.
• How long: single-dose exercise trials.
• Result: no pooled estimate; the authors state they were unable to make any firm conclusions, and that the side effects of using above the therapeutic dose outweigh the possible benefits.
• Funding: not stated.

Owing to the limitations of the published studies in this field, we were unable to make any firm conclusions with respect to the overall effect of pseudoephedrine and its ergogenic effect.

Where the research disagrees

Whether oral decongestants are worth taking for a cold

• Cochrane review authors, Deckx and colleagues (2016), systematic review of 15 randomised trials with GRADE ratings: They say the effect on congestion may be real but small and of unknown clinical relevance, on insufficient good-quality evidence. (Source 21)
• Authors of a 2024 narrative pharmacology review, narrative review of databases plus EudraVigilance pharmacovigilance data, with no stated systematic method for the comparison: They conclude antihistamines have a more favourable benefit-risk profile than vasoconstrictors such as pseudoephedrine for cold symptoms. (Source 15)

How much

• Reference intake: No reference intake exists, because this is a medicine and not a nutrient. The dose is set by the product’s label or by a prescriber. As a dated position, the Bayer Claritin-D 12 Hour US Drug Facts label published 8 December 2025 gives, for adults and children 12 years and over, a dose of 1 tablet every 12 hours. (Source 24)
• Upper limit: No tolerable upper intake level exists. As a dated position, the same Claritin-D 12 Hour US label published 8 December 2025 sets a ceiling of no more than 2 tablets in 24 hours, and directs consumers under 12 and those with liver or kidney disease to a doctor. (Source 24)
• Studied: The sport-performance review classed 60 to 120 mg as the therapeutic dose range and 180 mg or more as supratherapeutic. (Source 5)
• Studied: The exercise meta-analysis found a dose-response signal for time-trial and heart-rate effects only with doses above 170 mg. (Source 20)
• Studied: A bioavailability study gave four extended-release pseudoephedrine sulfate formulations to 20 healthy fasted volunteers. (Source 18)

A common belief, and what the research shows

The belief: Pseudoephedrine is a strong drug, so it must raise blood pressure dangerously.

What the research shows: The measured average rise is small. Pooled across 24 trials and 1,285 patients, systolic pressure rose about 1 mm Hg and heart rate about 3 beats per minute, and diastolic pressure did not change significantly. In people whose high blood pressure was already controlled the systolic rise was, in the review’s own word, of similar magnitude, about 1.2 mm Hg. What the same data show is that higher doses and immediate-release products push blood pressure up more, so the dose and the formulation matter more than the drug’s reputation. Separately, the serious events that do appear in the literature, such as ischaemic colitis, are case reports rather than trial findings, so their frequency is unknown.

Questions and answers

What is it?

Pseudoephedrine sulfate is a manufactured salt of pseudoephedrine, a stimulant amine. It is sold as a nasal decongestant. The Drug Facts panel of one US product, a 12-hour extended-release allergy tablet, lists pseudoephedrine sulfate 120 mg with the stated purpose ‘Nasal decongestant’ beside an antihistamine. Our own search of DailyMed found no single-ingredient pseudoephedrine sulfate US label at all, which is recorded in the notes for this batch rather than claimed from this label. (Source 25)

What does it do in the body?

It works indirectly. In isolated mouse and human atrial muscle, pseudoephedrine behaved as an indirect sympathomimetic, releasing stored noradrenaline rather than stimulating receptors itself; the giveaway was that cocaine, which blocks the reuptake of noradrenaline into nerve endings, attenuated the effect. That study used strips of heart muscle and measured force of contraction and beating rate, so it says nothing directly about the nose. The released noradrenaline narrows blood vessels, which is the accepted explanation for both the decongestant effect and the small rises in blood pressure and heart rate that human trials measure. (Source 1)

Is it good or bad for you?

Both, and one Cochrane review measures each side of it. For a decongestant combined with a painkiller, 73% of people on the active combination reported a benefit against 52% on the painkiller alone, which works out at about one extra person helped for every five treated. The same comparison produced significantly more adverse effects than the control on high-certainty evidence, about one extra person harmed for every 17 treated. So it is a short-term symptom treatment with a measurable benefit and a measurable cost. The review pooled decongestants generically and never isolates pseudoephedrine. (Source 13)

How do you get more of it?

It is bought, not eaten. Pseudoephedrine is sold over the counter, but in the United States its sale has been restricted to control illicit methamphetamine manufacture, which is why many cold and cough medicines switched to phenylephrine instead. A clinical pharmacology review argued those restrictions had little effect on methamphetamine harm while depriving the public of the more effective decongestant. (Source 26)

If it is harmful, what reduces it?

The body clears it, and stopping the drug is what the literature describes. In the four reported cases of ischaemic colitis linked to pseudoephedrine, all the women recovered once they stopped taking it, with supportive care, and none relapsed over the following 8 to 12 months. No antidote or elimination procedure is described for ordinary doses. (Source 11)

Why might someone be low in it or missing it?

The question does not apply in the nutrient sense: nobody is deficient in pseudoephedrine, because the body does not make it or need it. The reason someone might not be able to get it is regulatory. Sales were restricted in the United States to curb illicit methamphetamine production, and products were reformulated with phenylephrine, which the sole author of a clinical pharmacology review described as a poor substitute whose decongestant efficacy is unproven. (Source 26)

Which whole foods contain it or feed it?

No food contains it in any meaningful way. Pseudoephedrine does occur naturally as an alkaloid in Ephedra plants, alongside ephedrine, and plant studies measure how its content shifts with altitude and soil. Ephedra is a medicinal herb rather than a food, and the plant is not a practical or safe route to the drug. (Source 27)

What happens if you do not have it?

Nothing happens to the body, because it treats a symptom rather than filling a gap. The 2024 pharmacology review describes the common cold as the most frequent upper respiratory viral infection and as benign, though with a high socioeconomic burden; it does not say how long a cold lasts or that it resolves on its own, and we have not borrowed that from anywhere else. Without the drug, a blocked nose from a cold is less comfortable, not more dangerous. (Source 15)

How can you test for it?

There is no clinical test to tell anyone whether they need it. What can be measured is pseudoephedrine in urine. In sport, the World Anti-Doping Agency’s analytical urinary threshold for pseudoephedrine was set at 150 mcg/mL, a figure the authors call conservative, on the basis of two WADA-sponsored excretion studies in healthy people taking ordinary doses. A separate laboratory study cited elsewhere in this entry found that pseudoephedrine in urine is a common cause of a positive amphetamine screening result that mass spectrometry then fails to confirm. (Source 28)

References

1. Journal of cardiovascular pharmacology. Contractile Effects of Amphetamine, Pseudoephedrine, Nor-pseudoephedrine (Cathine), and Cathinone on Atrial Preparations of Mice and Humans. (abstract). 2024. PMID 38181215, DOI 10.1097/fjc.0000000000001536. Read the source
2. The Cochrane database of systematic reviews. Nasal decongestants in monotherapy for the common cold (abstract, Main results: multi-dose decongestant versus placebo paragraph). 2016. PMID 27748955, DOI 10.1002/14651858.cd009612.pub2. Read the source
3. The Cochrane database of systematic reviews. Oral antihistamine-decongestant-analgesic combinations for the common cold (abstract, Main results: antihistamine-decongestant paragraph). 2022. PMID 35060618, DOI 10.1002/14651858.cd004976.pub4. Read the source
4. Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology. Efficacy of Pseudoephedrine and Oxymetazoline in Preventing Otic Barotrauma: A Systematic Review and Meta-Analysis. (abstract: Results). 2026. PMID 41931637, DOI 10.1097/mao.0000000000004905. Read the source
5. BMJ open sport & exercise medicine. Effect of pseudoephedrine in sport: a systematic review. (abstract: Results). 2015. PMID 27900142, DOI 10.1136/bmjsem-2015-000066. Read the source
6. Bayer HealthCare LLC (US prescribing information via DailyMed, National Library of Medicine). CLARITIN-D 12 HOUR (loratadine and pseudoephedrine sulfate) tablet, extended release - US Drug Facts label, complete Warnings section. 2025. Read the source
7. Archives of internal medicine. Effect of oral pseudoephedrine on blood pressure and heart rate: a meta-analysis. (abstract). 2005. PMID 16087815, DOI 10.1001/archinte.165.15.1686. Read the source
8. International journal of sport nutrition and exercise metabolism. A comparison of caffeine versus pseudoephedrine on cycling time-trial performance. (abstract). 2013. PMID 23578950, DOI 10.1123/ijsnem.23.5.507. Read the source
9. Medicine, science, and the law. Acute psychosis due to the interaction of legal compounds--ephedra alkaloids in 'vigueur fit' tablets, caffeine in 'red bull' and alcohol. (abstract). 2001. PMID 11693229, DOI 10.1177/002580240104100410. Read the source
10. Nutrients. The Safety and Efficacy of Citrus aurantium (Bitter Orange) Extracts and p-Synephrine: A Systematic Review and Meta-Analysis. (abstract). 2022. PMID 36235672, DOI 10.3390/nu14194019. Read the source
11. The American journal of gastroenterology. Ischemic colitis associated with pseudoephedrine: four cases. (abstract: Results). 1999. PMID 10484004, DOI 10.1111/j.1572-0241.1999.01369.x. Read the source
12. Journal of psychopharmacology (Oxford, England). Acute psychosis following intravenous abuse of pseudoephedrine: a case report. (abstract). 1996. PMID 22302983, DOI 10.1177/026988119601000413. Read the source
13. The Cochrane database of systematic reviews. Oral antihistamine-decongestant-analgesic combinations for the common cold (abstract, Main results: analgesic-decongestant paragraph). 2022. PMID 35060618, DOI 10.1002/14651858.cd004976.pub4. Read the source
14. The American journal of gastroenterology. Ischemic colitis associated with pseudoephedrine: four cases. (abstract: Methods). 1999. PMID 10484004, DOI 10.1111/j.1572-0241.1999.01369.x. Read the source
15. Current medical research and opinion. Pharmacology of chlorphenamine and pseudoephedrine use in the common cold: a narrative review. (abstract). 2024. PMID 39484821, DOI 10.1080/03007995.2024.2424422. Read the source
16. Journal of forensic sciences. Evaluation of ephedrine, pseudoephedrine and phenylpropanolamine concentrations in human urine samples and a comparison of the specificity of DRI amphetamines and Abuscreen online (KIMS) amphetamines screening immunoassays. (abstract). 2004. PMID 14979364, DOI 10.1520/jfs2003233. Read the source
17. Annals of allergy, asthma & immunology : official publication of the American College of Allergy, Asthma, & Immunology. Comparative nasal airflow with loratadine-pseudoephedrine and fluticasone nasal spray for allergic rhinitis. (abstract: Results). 2021. PMID 34000435, DOI 10.1016/j.anai.2021.05.001. Read the source
18. Journal of pharmaceutical and biomedical analysis. In-vivo/in-vitro correlation of four extended release formulations of pseudoephedrine sulfate. (abstract). 1997. PMID 8953486, DOI 10.1016/s0731-7085(96)01834-1. Read the source
19. The Cochrane database of systematic reviews. Nasal decongestants in monotherapy for the common cold (abstract, Main results: single-dose decongestant versus placebo paragraph). 2016. PMID 27748955, DOI 10.1002/14651858.cd009612.pub2. Read the source
20. Sports medicine - open. Effects of pseudoephedrine on parameters affecting exercise performance: a meta-analysis. (abstract: Results). 2018. PMID 30291523, DOI 10.1186/s40798-018-0159-7. Read the source
21. The Cochrane database of systematic reviews. Nasal decongestants in monotherapy for the common cold. (abstract: Authors' conclusions). 2016. PMID 27748955, DOI 10.1002/14651858.cd009612.pub2. Read the source
22. Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology. Efficacy of Pseudoephedrine and Oxymetazoline in Preventing Otic Barotrauma: A Systematic Review and Meta-Analysis. (abstract: Conclusions). 2026. PMID 41931637, DOI 10.1097/mao.0000000000004905. Read the source
23. BMJ Open Sport & Exercise Medicine. Effect of pseudoephedrine in sport: a systematic review. (abstract: Conclusions). 2015. PMID 27900142, DOI 10.1136/bmjsem-2015-000066. Read the source
24. Bayer HealthCare LLC (US prescribing information via DailyMed, National Library of Medicine). CLARITIN-D 12 HOUR (loratadine and pseudoephedrine sulfate) tablet, extended release - US Drug Facts label, Directions section. 2025. Read the source
25. Bayer HealthCare LLC (US prescribing information via DailyMed, National Library of Medicine). CLARITIN-D 12 HOUR (loratadine and pseudoephedrine sulfate) tablet, extended release - US Drug Facts label, Active ingredient/Purpose and Uses sections. 2025. Read the source
26. British journal of clinical pharmacology. Substitution of phenylephrine for pseudoephedrine as a nasal decongeststant. An illogical way to control methamphetamine abuse. (abstract). 2007. PMID 17116124, DOI 10.1111/j.1365-2125.2006.02833.x. Read the source
27. PloS one. Ephedrine and pseudoephedrine in Ephedra saxatilis on the vertical altitude gradient changed in southern Tibet Plateau, China. (abstract). 2023. PMID 37624827, DOI 10.1371/journal.pone.0290696. Read the source
28. Drug testing and analysis. Determination of urinary concentrations of pseudoephedrine and cathine after therapeutic administration of pseudoephedrine-containing medications to healthy subjects: implications for doping control analysis of these stimulants banned in sport. (abstract). 2012. PMID 21548139, DOI 10.1002/dta.291. Read the source