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Category Names, Results, and Descriptions


Pancreatic alpha-Amylase Inhibitors (0) see Glycoside Hydrolase Inhibitors

Parasympatholytic Effect (0) see Parasympatholytics

Parasympatholytics (75) • Agents that inhibit the actions of the parasympathetic nervous system. The major group of drugs used therapeutically for this purpose is the MUSCARINIC ANTAGONISTS. MeSH

Parasympathomimetic Effect (0) see Parasympathomimetics

Parasympathomimetics (18) • Drugs that mimic the effects of parasympathetic nervous system activity. Included here are drugs that directly stimulate muscarinic receptors and drugs that potentiate cholinergic activity, usually by slowing the breakdown of acetylcholine (CHOLINESTERASE INHIBITORS). Drugs that stimulate both sympathetic and parasympathetic postganglionic neurons (GANGLIONIC STIMULANTS) are not included here. MeSH

Parenteral Nutrition Solutions (6) • Specialized solutions for PARENTERAL NUTRITION. They may contain a variety of MICRONUTRIENTS; VITAMINS; AMINO ACIDS; CARBOHYDRATES; LIPIDS; and SALTS. MeSH

Partial Opioid Agonists (0) see Analgesics, Opioid

PCSK9 Inhibitors (2)

Perfume (4) • A substance, extract, or preparation for diffusing or imparting an agreeable or attractive smell, especially a fluid containing fragrant natural oils extracted from flowers, woods, etc., or similar synthetic oils. (Random House Unabridged Dictionary, 2d ed) MeSH

Peripheral Nervous System (1)

Peripheral Nervous System Agents (883)

Peroxisome Proliferators (3) • A class of nongenotoxic CARCINOGENS that induce the production of hepatic PEROXISOMES and induce hepatic neoplasms after long-term administration. MeSH

Pesticide Synergists (3) • Chemicals that, while not possessing inherent pesticidal activity, nonetheless promote or enhance the effectiveness of other pesticides when combined. MeSH

Pesticides (376) • Chemicals used to destroy pests of any sort. The concept includes fungicides (FUNGICIDES, INDUSTRIAL); INSECTICIDES; RODENTICIDES; etc. MeSH

Pharmaceutic Aids (33) • Substances which are of little or no therapeutic value, but are necessary in the manufacture, compounding, storage, etc., of pharmaceutical preparations or drug dosage forms. They include SOLVENTS, diluting agents, and suspending agents, and emulsifying agents. Also, ANTIOXIDANTS; PRESERVATIVES, PHARMACEUTICAL; COLORING AGENTS; FLAVORING AGENTS; VEHICLES; EXCIPIENTS; OINTMENT BASES. MeSH

Pharmaceutical Solutions (27)

Pharmaceutical Vehicles (14) • A carrier or inert medium used as a solvent (or diluent) in which the medicinally active agent is formulated and or administered. (Dictionary of Pharmacy, 1986) MeSH

Phosphodiesterase 3 Inhibitors (6) • Compounds that specifically inhibit PHOSPHODIESTERASE 3. MeSH

Phosphodiesterase 4 Inhibitors (9) • Compounds that specifically inhibit PHOSPHODIESTERASE 4. MeSH

Phosphodiesterase 5 Inhibitors (9) • Compounds that specifically inhibit PHOSPHODIESTERASE 5. MeSH

Phosphodiesterase Inhibitors (68) • Compounds which inhibit or antagonize the biosynthesis or actions of phosphodiesterases. MeSH

Phosphoinositide-3 Kinase Inhibitors (1)

Phospholipase A2 Inhibitors (6)

Phosphorescent Agents (0) see Luminescent Agents

Photoaffinity Labels (5) • Biologically active molecules which are covalently bound to the enzymes or binding proteins normally acting on them. Binding occurs due to activation of the label by ultraviolet light. These labels are used primarily to identify binding sites on proteins. MeSH

Photosensitizing Agents (42) • Drugs that are pharmacologically inactive but when exposed to ultraviolet radiation or sunlight are converted to their active metabolite to produce a beneficial reaction affecting the diseased tissue. These compounds can be administered topically or systemically and have been used therapeutically to treat psoriasis and various types of neoplasms. MeSH

Photosensitizing Effect (0) see Photosensitizing Agents

Phytoestrogens (14) • PLANT EXTRACTS and compounds, primarily ISOFLAVONES, that mimic or modulate endogenous estrogens, usually by binding to ESTROGEN RECEPTORS. MeSH

Phytomitogens (0) see Mitogens

Pickling Agents (0) see Fixatives

Pigments, Inorganic (0) see Coloring Agents

Plant Growth Regulators (25) • Any of the hormones produced naturally in plants and active in controlling growth and other functions. There are three primary classes: auxins, cytokinins, and gibberellins. MeSH

Plasma Substitutes (5) • Any liquid used to replace blood plasma, usually a saline solution, often with serum albumins, dextrans or other preparations. These substances do not enhance the oxygen- carrying capacity of blood, but merely replace the volume. They are also used to treat dehydration. MeSH

Plasmin Inhibitors (0) see Antifibrinolytic Agents

Plasticizers (4) • Materials incorporated mechanically in plastics (usually PVC) to increase flexibility, workability or distensibility; due to the non-chemical inclusion, plasticizers leach out from the plastic and are found in body fluids and the general environment. MeSH

Platelet Aggregation Inhibitors (145) • Drugs or agents which antagonize or impair any mechanism leading to blood platelet aggregation, whether during the phases of activation and shape change or following the dense-granule release reaction and stimulation of the prostaglandin-thromboxane system. MeSH

Platelet Aggregation Inhibitors (1)

Platelet Antagonists (0) see Platelet Aggregation Inhibitors

Platelet Inhibitors (0) see Platelet Aggregation Inhibitors

Poisons (34) • Substances which, when ingested, inhaled, or absorbed, or when applied to, injected into, or developed within the body in relatively small amounts may, by their chemical action, cause damage to structure or disturbance of function. (From Dorland, 27th ed) MeSH

Poly(ADP-ribose) Polymerase Inhibitors (22) • Chemicals and drugs that inhibit the action of POLY(ADP-RIBOSE)POLYMERASES. MeSH

Potassium Channel Blockers (17) • A class of drugs that act by inhibition of potassium efflux through cell membranes. Blockade of potassium channels prolongs the duration of ACTION POTENTIALS. They are used as ANTI-ARRHYTHMIA AGENTS and VASODILATOR AGENTS. MeSH

Potassium Depleting Diuretics (0) see Sodium Chloride Symporter Inhibitors

Potassium Ionophores (2)

Preservatives, Pharmaceutical (7) • Substances added to pharmaceutical preparations to protect them from chemical change or microbial action. They include ANTI-BACTERIAL AGENTS and antioxidants. MeSH

Progestin Effect (0) see Progestins

Progestin Synthesis Inhibitors (0) see Steroid Synthesis Inhibitors

Progestins (16) • Compounds that interact with PROGESTERONE RECEPTORS in target tissues to bring about the effects similar to those of PROGESTERONE. Primary actions of progestins, including natural and synthetic steroids, are on the UTERUS and the MAMMARY GLAND in preparation for and in maintenance of PREGNANCY. MeSH

Prolonged-Action Preparations (0) see Delayed-Action Preparations

Prolyl-Hydroxylase Inhibitors (1)

Prostaglandin Antagonists (13) • Compounds that inhibit the action of prostaglandins. MeSH

Protease Inhibitors (251) • Compounds which inhibit or antagonize biosynthesis or actions of proteases (ENDOPEPTIDASES). MeSH

Proteasome Inhibitors (3)

Protective Agents (417) • Synthetic or natural substances which are given to prevent a disease or disorder or are used in the process of treating a disease or injury due to a poisonous agent. MeSH

Protein Kinase Inhibitors (126) • Agents that inhibit PROTEIN KINASES. MeSH

Protein Synthesis Inhibitors (65) • Compounds which inhibit the synthesis of proteins. They are usually ANTI-BACTERIAL AGENTS or toxins. Mechanism of the action of inhibition includes the interruption of peptide-chain elongation, the blocking the A site of ribosomes, the misreading of the genetic code or the prevention of the attachment of oligosaccharide side chains to glycoproteins. MeSH

Proton Ionophores (3) • Chemical agents that increase the permeability of CELL MEMBRANES to PROTONS. MeSH

Proton Pump Inhibitors (16) • Compounds that inhibit H(+)-K(+)-EXCHANGING ATPASE. They are used as ANTI-ULCER AGENTS and sometimes in place of HISTAMINE H2 ANTAGONISTS for GASTROESOPHAGEAL REFLUX. MeSH

Provitamins (5)

Psychotropic Drugs (327) • A loosely defined grouping of drugs that have effects on psychological function. Here the psychotropic agents include the antidepressive agents, hallucinogens, and tranquilizing agents (including the antipsychotics and anti-anxiety agents). MeSH

Pulmonary Surfactants (3) • Substances and drugs that lower the SURFACE TENSION of the mucoid layer lining the PULMONARY ALVEOLI. MeSH

Purinergic Agents (4)

Purinergic Agonists (16)

Purinergic Antagonists (34)

Purinergic P1 Receptor Agonists (15) • Compounds that bind to and stimulate PURINERGIC P1 RECEPTORS. MeSH

Purinergic P1 Receptor Antagonists (22) • Compounds that bind to and block the stimulation of PURINERGIC P1 RECEPTORS. MeSH

Purinergic P2 Receptor Antagonists (12) • Compounds that bind to and block the stimulation of PURINERGIC P2 RECEPTORS. MeSH

Purinergic P2X Receptor Antagonists (2)

Purinergic P2Y Receptor Antagonists (10) • Compounds that bind to and block the stimulation of PURINERGIC P2Y RECEPTORS. Included under this heading are antagonists for specific P2Y receptor subtypes. MeSH

Purinergic P2Y1 Receptor Antagonists (0) see Purinergic P2Y Receptor Antagonists

Purinergic P2Y12 Receptor Antagonists (0) see Purinergic P2Y Receptor Antagonists

Purinergic P2Y2 Receptor Antagonists (0) see Purinergic P2Y Receptor Antagonists

Pustulants (0) see Irritants

Pyrogens (1) • Substances capable of increasing BODY TEMPERATURE and cause FEVER and may be used for FEVER THERAPY. They may be of microbial origin, often POLYSACCHARIDES, and may contaminate distilled water. MeSH

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Last updated: Sep 2022