Ethinyl estradiol is a synthetic derivative of the natural estrogen estradiol. It is one of two estrogens currently used in oral contraceptive pills. The other, mestranol, is converted to ethinyl estradiol before it is biologically active. Ethinyl estradiol and norethindrone are used together as an oral contraceptive agent. Estrogens diffuse into their target cells and interact with a protein receptor. Target cells include the female reproductive tract, the mammary gland, the hypothalamus, and the pituitary. Estrogens increase the hepatic synthesis of sex hormone binding globulin (SHBG), thyroid-binding globulin (TBG), and other serum proteins and suppress follicle-stimulating hormone (FSH) from the anterior pituitary. This cascade is initiated by initially binding to the estrogen receptors. The combination of an estrogen with a progestin suppresses the hypothalamic-pituitary system, decreasing the secretion of gonadotropin-releasing hormone (GnRH). Used for treatment of moderate to severe vasomotor symptoms associated with the menopause, female hypogonadism, prostatic carcinoma-palliative therapy of advanced disease, breast cancer, as an oral contraceptive, and as emergency contraceptive.

Benzhydrocodone is a prodrug of hydrocodone. Benzhydrocodone is formed by covalently bonding hydrocodone to benzoic acid. Benzhydrocodone itself is not pharmacologically active, but must be metabolized to hydrocodone by enzymes in the intestinal tract to optimally deliver its pharmacologic effects. Hydrocodone is a full agonist of the opioid receptors with a higher affinity for the mu-opioid receptor. Upon binding, hydrocodone produces an analgesic effect with no ceiling. APADAZ a combination of benzhydrocodone and acetaminophen is FDA approved and indicated for the short-term (no more than 14 days) management of acute pain severe enough to require an opioid analgesic and for which alternative treatments are inadequate. APADAZ, even when taken as recommended, can result in addiction, abuse, and misuse, which can lead to overdose and death.

Pethidine, also known as meperidine and Demerol, a narcotic analgesic that can be used for the relief of most types of moderate to severe pain, including postoperative pain and the pain of labor. Meperidine is an opioid agonist with multiple actions qualitatively similar to those of morphine. Most common adverse reactions were lightheadedness, dizziness, sedation, nausea, vomiting, and sweating. Pethidine has serious interactions that can be dangerous with monoamine oxidase inhibitors (e.g., furazolidone, isocarboxazid, moclobemide, phenelzine, procarbazine, selegiline, tranylcypromine). Pethidine can interact with muscle relaxants, some antidepressants, benzodiazepines, and ethanol.

Estradiol benzoate is the synthetic benzoate ester of estradiol, a steroid sex hormone vital to the maintenance of fertility and secondary sexual characteristics in females. As the primary, most potent estrogen hormone produced by the ovaries, estradiol binds to and activates specific nuclear receptors. This agent exhibits mild anabolic and metabolic properties, and increases blood coagulability. Although estradiol benzoate is not approved by the FDA for use in humans in the United States, it is approved for veterinary use as a subdermal implant both alone (CELERIN®) and in combination with the anabolic steroid trenbolone acetate (SYNOVEX® Plus).

Phenytoin is an anti-epileptic drug. Phenytoin has been used with much clinical success against all types of epileptiform seizures, except petit mal epilepsy. Phenytoin is a available for oral administration (tablets, capsules, suspension). CEREBYX® (fosphenytoin sodium injection) is a prodrug intended for parenteral administration; its active metabolite is phenytoin. CEREBYX should be used only when oral phenytoin administration is not possible. Although several potential targets for phenytoin action have been identified within the CNS (Na-K-ATPase, the GABAA receptor complex, ionotropic glutamate receptors, calcium channels and sigma binding sites) to date, though, the best evidence hinges on the inhibition of voltage-sensitive Na channels in the plasma membrane of neurons undergoing seizure activity.

Progesterone is indicated in amenorrhea and abnormal uterine bleeding due to hormonal imbalance in the absence of organic pathology, such as submucous fibroids of uterine cancer. Progesterone, converted from pregnenolone, also serves as an intermediate in the biosynthesis of gonadal steroid hormones and adrenal corticosteroids. Progesterone is a naturally occurring steroid that is secreted by the ovary, placenta, and adrenal gland. In the presence of adequate estrogen, progesterone transforms a proliferative endometrium into a secretory endometrium. Progesterone is necessary to increase endometrial receptivity for implantation of an embryo. Once an embryo is implanted, progesterone acts to maintain a pregnancy. Progesterone shares the pharmacological actions of the progestins. Progesterone binds to the progesterone and estrogen receptors. Target cells include the female reproductive tract, the mammary gland, the hypothalamus, and the pituitary. Once bound to the receptor, progesterone will slow the frequency of release of gonadotropin releasing hormone (GnRH) from the hypothalamus and blunt the pre-ovulatory LH (luteinizing hormone) surge. In women who have adequate endogenous estrogen, progesterone transforms a proliferative endometrium into a secretory one. Progesterone is metabolized primarily by the liver largely to pregnanediols and pregnanolones. Pregnanediols and pregnanolones are conjugated in the liver to glucuronide and sulfate metabolites. Progesterone metabolites that are excreted in the bile may be deconjugated and may be further metabolized in the gut via reduction, dehydroxylation, and epimerization. Common progesterone side effects may include: drowsiness, dizziness; breast pain; mood changes; headache; constipation, diarrhea, heartburn; bloating, swelling in your hands or feet; joint pain; hot flashes; or vaginal discharge.

Colchicine is an alkaloid obtained from the plant colchicum autumnale (also known as "meadow saffron"). Colchicine is an alternative medication for those unable to tolerate NSAIDs in gout. Mechanism of action of colchicine is inhibition of microtubule polymerization by binding to tubulin. Availability of tubulin is essential to mitosis, so colchicine effectively unctions as a "mitotic poison" or spindle poison.

Pilocarpine is an alkaloid extracted from plants of the genus Pilocarpus. The drug stimulates the muscarinic receptors (especially M3, which is expressed in smooth muscles and glands) and thus induces salivation, hypertension and water intake. Pilocarpine was appoved by FDA for the alleviation of symptoms of xerostomia in patients who have undergone radiation therapy to their head and neck cancer and in patients with Sjogren's Syndrome. Ophthalmic solution of the drug is prescribed for the treatment of glaucoma, ocular hypertension, postoperative elevated intraocular pressure, etc.

Morphine is one of the most important and widely used opioid for the treatment of chronic and acute pain: the very wide interindividual variability in the patients’ response to the drug may have genetic derivations. Sulphate salt of morphine sold under the many brand names, one of them, DURAMORPH, which is indicated for the management of pain severe enough to require use of an opioid analgesic by intravenous administration, and for which alternative treatments are not expected to be adequate. In addition for the epidural or intrathecal management of pain without attendant loss of motor, sensory, or sympathetic function. Morphine is a full opioid agonist and is relatively selective for the mu-opioid receptor, although it can bind to other opioid receptors at higher doses. The principal therapeutic action of morphine is analgesia. Like all full opioid agonists, there is no ceiling effect for analgesia with morphine. The precise mechanism of the analgesic action is unknown. However, specific CNS opioid receptors for endogenous compounds with opioid-like activity have been identified throughout the brain and spinal cord and are thought to play a role in the analgesic effects of this drug. Morphine has a high potential for addiction and abuse. Common side effects include drowsiness, vomiting, and constipation. Caution is advised when used during pregnancy or breast-feeding, as morphine will affect the baby.

Pyrantel is an anthelmintic, which acts as an agonist of nicotinic receptors (AChRs) of nematodes and exerts its therapeutic effects by depolarizing their muscle membranes. It is used to treat a number of parasitic worm infections. This includes ascariasis, hookworm infections, enterobiasis (pinworm infection), trichostrongyliasis and trichinellosis. Common adverse reactions include diarrhea, nausea, vomiting, dizziness, headache and somnolence.