Pseudoephedrine: A Good Appetite Suppressant?
Bodybuilders, dieters and athletes are always on the look out for that one compound that will help them reach their physical goals. The market is a very complex one. With the supplement industry not requiring FDA approval on their products, compounds are being released for every niche and purpose without any true studies done for safety or efficacy. Diet aids seem to have the biggest advantage for this with the ability to take advantage of those people who are looking for anything out there that can help them shed those extra 10-15 pounds. With new Jamaican Jambalayan derived Hoodia products being released, people are starting to forget products that already exist in the marketplace which have already been proven to be safe and efficacious.
A pharmaceutical product which has gained much popularity as of lately, however not in a good way, is Pseudoephedrine. Pseudoephedrine, being FDA approved as an over-the-counter oral decongestant, is closely related to the once powerful weight loss supplement ephedrine. The truth was ephedrine (and its ephedra alkaloids) worked. It not only promoted thermogensis in humans, but was a potent appetite suppressant. Unfortunately today, ephedra is not an easy compound to obtain. It is scarcely available as an OTC pharmaceutical, used as a bronchodilator, and in some states is still available as an herbal product. Pseudoephedrine on the other hand is still widely available in the U.S., and even though it does have some restrictions, it can still be obtained with quite ease. In this article we will discuss the pharmaceutical properties of pseudoephedrine, restrictions on its purchase, and its use as an appetite suppressant.
Pseudoephedrine is a sympathomimetic amine and a (1S,2S)- diasteromer of ephedrine. It is available over-the-counter as a decongestant and is commonly found in combination with other medications (ie. antihistamines, cough and cold preparations). Being a sympathomimetic amine, it stimulates the sympathetic nervous system by displacing norepinephrine from storage vesicles in presynaptic neurons to activate postsynaptic adrenergic receptors. Pseudoephedrine is also an ?1a, ?2a and ?2-receptor agonist. By selectively activating the alpha receptors in the mucosa tract of the respiratory and nasal pathways, pseudoephedrine produces vasoconstriction shrinking membranes and relieving congestion. Activation of the beta2 receptor causes bronchodilation, which is relaxation of the bronchial smooth muscle, which allows the user to breathe easier. Pseudoephedrine has less pressor activity and a lower affinity for the central nervous system when compared to ephedrine so one should not to see much, if any, of a stimulating effect at recommended doses.
Pseudoephedrine is readily absorbed from the GI tract with very little first pass metabolism. It is excreted mostly unchanged in the urine with few metabolites from being metabolized hepatically. The half-life is approximately 4-6 hours being dependant on urinary pH. If urine pH is less than 6 then the half-life may be decreased, as opposed to being increased when the urine pH is greater than 8. Pseudoephedrine has also been shown not to bind to plasma protein when the concentration is between 50-2000ng/mL.
Pseudoephedrine is commonly used for the following:
- Relief from nasal or sinus congestion;
- Relief of ear congestion;
- Treatment of vasomotor rhinitis (non-allergic rhinitis); and
- First line treatment for Priapism (erection lasting more then four hours)
Potential ADR’s are as follows:
- CNS Stimulation
- Elevation of blood pressure
Few events have been reported of hallucinations and stroke, similar to ephedrine.
Pseudoephedrine should not be used if you are currently taking an MAO-I or any anti-hypertensive medications (i.e. beta-blockers).
Pseudoephedrine is available in different strengths and dosage forms. The most popular OTC version is the 30mg tablet. Normal dosing on this is one 30mg tablet, every four hours. Also available are extended-release tablets in 120mg and 240mg. The 120mg tablet should be dosed one tablet every 12 hours and the 240mg tablet should be taken only once a day. The maximum advised dose for pseudoephedrine is 240mg per 24 hours.
Restrictions on Purchase
With the recent increase in illicit methamphetamine use, pseudoephedrine is being sought after by ‘home cooks’ to use in meth production. Since its availability was once quite easy and the synthesis could be completed on kitchen stoves, the government had to step in and limit the sales of pseudoephedrine in an effort to limit illegal methamphetamine production. Currently, only pharmacies are allowed to sell pseudoephedrine and it must be kept behind the counter. For each purchase, the customer must present a government issued photo ID and it must be recorded in a computer or a log book. The government has also limited the amount of pseudoephedrine that could be purchased per day and per month. Individual purchases are limited to 3.6 grams per day, and no more then 9 grams being purchased within a 30-day period. While this does limit the amount that you can experiment with, a user will still be able to consume 300mg of pseudoephedrine a day.
Pseudoephedrine as a Diet Aid
Alright well now on to the fun stuff. Sympathomimetic stimulants have long been used clinically as appetite suppressants for the short-term treatment of obesity (ie. Phentermine). Hypothalamic appetite centers in the brain control both central and peripheral signals. This center can be turned on and off by the use of anorectic agents which includes noradrenergic, serotonergic, and dopaminergic drugs. Pseudoephedrine, ephedrine, and phenylpropanolamine (norephedrine) all increase norepinephrine adrenergic neurotransmitter concentrations thus activating hypothalamic centers, which results in decreased appetite and food intake. They do this by stimulating the excitatory alpha-1 and beta-2 receptors which suppress appetite; stimulation of the inhibitory alpha-2 receptor on the other hand will actually work to increase appetite.
Pseudoephedrine may not be as strong as ephedrine or PPA, however it does work. Tolerance, just as with any other stimulant, is a strong possibility so it would be best if the drug was cycled. The most efficacious dosing is to take one 120mg extended-released tablet, twice a day, or one 240mg extended-released tablet per day. One could also take 30mg tablets spread throughout the day however anecdotal reports have said for this not to be as effective as using the extended-release form.
‘Stacking’ or combining pseudoephedrine with other products may work to increase it efficacy. Caffeine is a competitive inhibitor of the enzyme cAMP-phosphodiesterase which metabolizes cyclic AMP (cAMP) to its non-active form. One mechanism behind how norepinephrine works is that it increases the levels of cAMP. Thus by consuming caffeine along with the pseudoephedrine it can help not only to prolong, but also intensify, the effect of norepinephrine. One could start out with 100mg of caffeine twice a day, and gradually work up to 200mg twice a day. However with the amount of caffeine people are consuming now-a-days tolerance may already be a bit high and 100mg may not have much of an effect.
Tolerance should be assessed by starting at a lower dose of pseudoephedrine before increasing it due to the fact some people notice an increase in heart-rate, blood pressure, and even some neuropsychiatric effects (hallucinations). A dosing scheme should be tailored to your tolerance, here is an example:
Week 1: 120mg pseudoephedrine once a day with 100mg caffeine twice a day
Week 2: 240mg pseudoephedrine once a day (or 120mg twice a day) with a 100mg caffeine twice a day.
Week 3-6: 240mg pseudoephedrine once a day (or 120mg twice a day) with 200mg caffeine twice a day.
Cycle off for 2 weeks and repeat.
In conclusion, I hope that this article will start generating more feedback on the use of pseudoephedrine as an appetite suppressant. As long as you are a responder, this should be an efficacious and safe product to add to your dieting needs. On top of that, it will allow you to breathe easier while working out! If you have any questions or feedback please email me at [email protected]. I would love to hear them.
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