22 votes
Accepted

Is lysergic acid diethylamide (LSD) metabolized in the body?

Short answer LSD appears to be enzymatically broken down in the liver. Background First off, hormones do not break down anything; enzymes are the work horses that mediate metabolism. According to a ...
AliceD's user avatar
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8 votes

Is lysergic acid diethylamide (LSD) metabolized in the body?

LSD is metabolized in the liver in humans by enzymes of the Cytochrome P450 hemoprotein. The specific enzymes are CYP3A4 and CYP2D6. CYP2D6 is generally regarded as non-inducible (meaning there ...
Drunken Code Monkey's user avatar
8 votes
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Does LSD "stay" in your fat storage and then "returns" back?

I've heard this rumor for years, both from pro- and anti-drug people, and it is not true. According to this review of LSD's pharmacology, its half-life in the body is about 5 hours, with it being ...
MattDMo's user avatar
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7 votes

Longevity and extent of transfection after SARS-COV-2 vaccination with Janssen

Both the AstraZeneca (AZ) and Janssen (J) vaccines against SARS-CoV-2 work by using what is known as a viral vector to generate an immune response. In both cases these vaccines use an Adenovirus as ...
bob1's user avatar
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7 votes
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What is the motivation behind fluorinated pharmaceuticals?

Fluorine has a combination of unique chemical properties, which makes it very useful in drug design : It is small, such that replacing a C-H with a C-F is often possible, from a sterical point of ...
Eliane B.'s user avatar
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6 votes
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Derivation for drug half life

Well, $Cl = R/Cp$ is correct, but $R$ is not $Cp \cdot k$. Given $X(t)$, the actual quantity (ie weight or moles) of drug in the system, $R$ should have the dimension of $\frac{dX(t)}{dt}$, that is $...
Eliane B.'s user avatar
  • 1,145
5 votes
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Concentration of active ingredient

Exponential decay is a commonly observed phenomenon in nature where the rate of decay is directly proportional to the amount of stuff you start with. If you have twice as much stuff, it decays twice ...
Bryan Krause's user avatar
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4 votes
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How to make GABA pass the blood brain barrier?

Short answer Chemical reversible shielding of the aminogroup in GABA seems to be sufficient to get it into the brain as a Trojan horse. Background Given that you ask ...how to make GABA pass ...
AliceD's user avatar
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4 votes
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Does ingestion of alcohol with methylphenidate make it act more like dexmethylphenidate?

Does the ingestion of alcohol, when taking (racemic) methylphenidate can actually make it more potent? It is the 2011 study you've mentioned that answers most of the question. In the study, ethanol ...
Jan's user avatar
  • 8,079
4 votes

What is this Japanese study of the Pfizer vaccine measuring?

It looks like they're using the luciferase RNA as a substitute for the actual mRNA used in the vaccine because, since luciferase emits light when exposed to its substrate, it's easy to measure the ...
Luigi's user avatar
  • 3,338
4 votes
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Why does the Scatchard plot have a negative gradient?

I think you probably misunderstand which quantities exactly are represented on the Scatchard plot. Let's start from the beginning. Binding between a receptor, $\mathrm R$, and a ligand, $\mathrm L$, ...
Domen's user avatar
  • 1,932
3 votes
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How do prodrugs exactly work? Are there multiple varieties of prodrugs?

Prodrugs are extremely common; we often don't even think of some of them as prodrugs unless we're also familiar with the metabolite. Psilocybin, for example, is a prodrug; the active molecule is ...
Bryan Krause's user avatar
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3 votes
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Why is alcohol such a weak drug?

As Christiaan already pointed out, this depends on the pharmacokinetic and pharmacodynamic parameters. The effective drug concentration depends on the drug-receptor association constant and the drug ...
WYSIWYG's user avatar
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3 votes

Estimation of tissue-partition coefficients and clearance for liposomic nanoparticles

Regarding the tissue partition coefficient, Li et al. said: "By using such a parameter, it is assumed that there is the same transfer kinetics of nanoparticles from blood into tissues as from tissues ...
Polymania's user avatar
  • 326
3 votes
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Bioavailability -- what is the effect of absorption rate?

I think you will frequently find that measures in biology are not defined in a consistent manner, largely because experimental constraints often require a different operational definition. People ...
Bryan Krause's user avatar
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2 votes
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How could this molecule affect the body? (Lysergic acid derivative)

That is lysergic acid piperidide, an analog of lysergic acid diethylamide (LSD). According to Wikipedia, it is an agonist of the 5-HT2A receptor, but is much less potent than LSD.
canadianer's user avatar
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2 votes
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How does having spare receptors change ED50 in an irreversible agonist

Irreversible antagonism is like removing receptors. If there are spare receptors, maximum effect, or any effect level, can be recovered with more ligand (because displacing the irreversible ligand is ...
Eliane B.'s user avatar
  • 1,145
2 votes
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Cell nanoparticle dynamics within blood

To go the PBPK route: I would recommend using the organism parameters and structure from the whole body platform model by Shah and Betts. Shah, D.K. & Betts, A.M. J Pharmacokinet Pharmacodyn (...
Polymania's user avatar
  • 326
2 votes

Can 5 alpha reductase inhibitor drugs work for life or do they lose effectiveness?

As noted in a comment, a truly thorough answer to this question would require one or more books (1,2) or scientific journals (3), but a simpler, necessarily incomplete answer can be provided. The ...
Demosthenes' pars triangularis's user avatar
2 votes
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Does Povidone-Iodine that penetrates through the skin stays in the body (cells, liver etc)?

Your source (DrugBank via PubChem) is describing the typical pharmacokinetic information (ADME, absorption, distribution, metabolism, excretion) on Providine-Iodine, under the assumption it is not ...
De Novo's user avatar
  • 8,791
2 votes
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Does body fat percentage effect storage of fat soluble compounds?

Does body fat percentage effect storage of fat soluble compounds? Generally, yes. Phenytoin, an anti-seizure drug, provides a good and well studied example. The key issue here is that, for ...
De Novo's user avatar
  • 8,791
2 votes

Why use a logarithmic scale when plotting pharmacodynamics/kinetics?

There could be several reasons for this. You mention in the comments that your plot of interest is the concentration-time profile. As you can see, plotting the logarithm of concentration vs time ...
mhh's user avatar
  • 176
2 votes
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What is this Japanese study of the Pfizer vaccine measuring?

There are at least three types of studies being described. In a paragraph before the quoted one, they talk about testing for the PEGylated lipids ALC-0315 and ALC-0159 in plasma, liver, urine, and ...
mgkrebbs's user avatar
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2 votes
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What determines if a compound is primarily taken up by the lymphatic extensions rather than the portal vein blood supply in the intestinal villi?

The path used for a particular compound is determined by several factors: Affinity for Plasma Proteins: Compounds with a high affinity for plasma proteins are more likely to remain in the bloodstream ...
Robert Long's user avatar
1 vote

Can you find the mass of drug X remaining in the body after an oral dose with only bioavailability and half-life?

Unfortunately, it is not so easy, the easy calculation you suggested might be a good approximation if the drug was administered intravenously via bolus, but for oral administration, as you say in the ...
Robert Long's user avatar
1 vote
Accepted

Area under the curve in a drug concentration curve

This definition of AUC is non-standard. The usual definition does not involve the MIC or 24h: it is the area (~ integral) of the plasma concentration curve as a function of time, from first ...
Eliane B.'s user avatar
  • 1,145
1 vote

Difference between rate of elimination and clearance?

Clearance is a measure of the volume of plasma from which something is removed, per unit time. For instance, it could be 2 mL/min, meaning that every minute, a two-milliliter of drug plasma is cleared....
416E64726577's user avatar
1 vote

Why does plasma protein saturation of a drug increase its volume of distribution and clearance rate?

First a couple of clarifications: You wrote: For the distribution volume to increase, unbound drug concentration in plasma should stay constant while tissue drug concentration has to increase when ...
Adhish's user avatar
  • 1,307
1 vote

How are drugs distributed in regards to bone marrow?

How are drugs distributed into any tissue, and what affects it? Note that there are no general answers, and that this is highly dependent on the drug in question. Active or passive transport Is your ...
mhh's user avatar
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