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Would you be able to explain what effects constipation has on pharmacokinetics? Also what else has effects on pharmacokinetics?


Dear John,

 There are 4 parts to pharmacokinetics: absorption, distribution, metabolism, and elimination.  If a patient is constipated, that could be a sign of having inadequate hydration (ie lack of water or fluids passing through the person) or poor fiber intake.  This could cause reduced elimination, or how the body gets rids of medication.  The body gets rid of medication in a number of ways, which includes through urination, bowel movement, sweat, etc.  Constipation could allow the drug concentrations to build up in the patient's bloodstream and delay its release from the body's system.  Metabolism involves how a drug is broken down into the body's system, such as by the liver.  Constipation due to dietary reasons may slow down the breaking down of the medication, since drug metabolism may be poorer in patients with poor diets.  Distribution involves how a drug travels through the body's system, whether through the bloodstream, GI system, etc, to do its job.  For example, probiotics such as lactobacillus work in the gut to aid in dietary ingestion.  Distribution may be slowed down if inadequate fluid intake is causing the constipation.  There are many oral drugs on the market that require patients to take with a full glass of water to help ensure the drug goes to where it needs in the body to do its job.  Absorption involves how well the body's system takes up the drug upon administration.  Absorption may be poorer in patients with constipation due to poor hydration since adequate hydration may be needed for drugs to be absorbed properly.  For example, iron is only about 60% absorbed by patients.  One way of enhancing absorption is by drinking a full 8 ounce glass of orange juice with the iron.  The increases iron's absorption but also helps to relieve constipation due to orange juice containing fiber.

Age, gender, race, overall health, nutrition, kidney functioning, and liver functioning all have effects of pharmacokinetics.  


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Nanaz Khosrowshahi


Being a pharmacist, I can answer questions on medications. This includes how drugs work in the body, drug interactions, drug side effects, warnings and precautions to take when using certain medications, dosage forms and strengths, management of overdosing, storage of medications, drug administration, contraindications, and drug indications. I am able to guide them on lab work that needs to be drawn and monitored while on certain medications. I am able to help patients save money when purchasing medications by directing them to cost-effective therapies. I am able to answer questions on federal laws governing pharmacy practice in the United States. I am unable to answer questions legally as if I am diagnosing the patient's disease or illness. For example, if a patient stated he had upper flank pain, I am unable to say he definitely has a urinary tract infection. However, I am able to direct the patient to the correct next step, which is to call his physician with such a side effect.


I have been a licensed pharmacist since 2007, holding licenses in CT and MA. I have a PHARM.D from an accelerated pharmacy school program. Currently, I work at the Hebrew Home and Hospital in West Hartford, CT as a pharmacist. I am a well-rounded pharmacist, with experience in long-term care, IV home infusion, retail, hospital, and hospice. I serve as the pharmacy unit coordinator for Mass Dispensing Area #31 in CT, where I am called upon as a volunteer pharmacist in case of public emergencies, such as anthrax threats. I helped run the swine flu vaccine clinic in 2009. I am on the Editorial Advisory Board for Pharmacy Today, a publication of the American Pharmacists Association. My position on the board runs for three years. Every month I make suggestions and offer ideas that would help improve the magazine. I have undergone extra training to administer vaccines to patients, which is training that only a certain percentage of registered pharmacists in the country have.

American Pharmacists Association 2007

Massachusetts College of Pharmacy and Health Sciences, Worcester, MA- PHARM.D 2007 University of California, Irvine- BA psychology 2001 cum laude

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