Medication Basics

How is a Medication Dosage Determined?

The Federal Drug Administration (FDA) determines the dosing of medication needed to treat a condition based on clinical research. After completing years of clinical trials documenting patient outcomes and drug safety, the FDA approves a drug’s release for use by the public.

The drug is approved only to treat the conditions covered during the clinical trials because those are the only ones where data supports public safety.

If a doctor prescribes a drug in a manner not approved by the FDA, he has prescribed it illegally and is subject to possible criminal charges for violating this Code of Conduct. Furthermore, he could permanently lose his practice to work as a physician under the rules established by the Board of Pharmacy.

Important Facts About Dosage

The dosage is the amount of medication you need to take and must be exact. Being off even a little with some medications can have serious consequences. Therefore, here are some important facts to keep in mind about dosages.

  • Adults and children do not take the same amount of medicine. Weight determines the dosing for children. Although adult dosage is typically not based on weight, ask your doctor if it needs consideration if your adult family member is underweight or overweight.
  • Liquid dosing usually appears as ml volume but may be written as teaspoons or tablespoons. Therefore, you will want to have measuring utensils available that allow you to see ML measurements.
  • Always measure by the bottom of the bubble lying on top of the line when you look at the side of the measuring device if you have a liquid to measure.
  • If you need to convert measurements from one type of measure to another, contact your pharmacist for assistance. The conversion formula must often include a number based on the device used to administer the medication. You’ll get the calculation wrong if you don’t know that number. 
  • You must use the metric system to calculate conversion because all medication dosages use metrics system formulas.
  • Always give the exact amount of medication. The amount prescribed is usually determined based on age and weight. If you give a different amount, you could jeopardize the effectiveness of the action or cause unwanted side effects.
  • If you apply a patch to the skin, always remove the old patch and clean off what was left behind. If you don’t, you could cause the person to get a toxic medication build-up over time. Also, be careful and do not get the medicine on your skin. You will get the same effect as the person supposed to get the medicine.
  • If you’re giving medicines that say enteric-coated, do NOT open them to put in with other food. If you do, they get absorbed before they hit the intestine and lose their effectiveness. The Enteric coating keeps them from initiating the stomach lining before it hits the intestine because it cannot be absorbed correctly before getting there.
  • If giving IM (intramuscular) injections versus SQ (subcutaneous) injections, be clear about how you give them. Order one instead of the other based on absorption speed. Usually, the subcutaneous indicates the need for slow absorption, best accomplished using fatty tissue injection. If you give it into the muscle, it will be absorbed too quickly, not last as long as it should, or cause overdose reactions.
Ways to Give Medicines (Route)

The way you give medication is called the route. Medications are given by mouth, intramuscularly, subcutaneously, rectally, through a tube into the stomach, under the tongue, held in the cheek, given as eye drops, nose drops, inhaled, swallowed, injected, using a patch, and a few other ways.

If you need to change the route of administration, call the doctor to find out if the dose needs to change. Often the dosage is based on how the medication is absorbed. If the route changes, the amount may need to be increased or decreased accordingly.

 Frequency and Duration

Try to evenly space multi-dose drugs apart when you take them throughout the day so that the effects of the drug can keep a consistent blood level as they work within the body.

Complete taking medications like antibiotics until all the medicine is gone, even if you feel well. It would be best to have the full dose to ensure the germs are all dead. However, if you have a prescription for pain pills or something to relieve a symptom that no longer exists, stop the medication and don’t refill it even if you have more refills available. If you are in doubt about stopping the medicine, ask your doctor.

Don’t take medication if you no longer need it. You will build a tolerance to it and need more to produce the same effect. Your goal should always be to decrease the number of drugs you take so that your body continues to create its natural supply of chemicals rather than relying on external sources for healing.

What are Side Effects?

All drugs have side effects. Manufacturers develop drugs with a specific purpose, such as treating muscle spasms. As the chemicals work together to stop the muscle spasms, the intended effect occurs – the muscle spasms stop. However, some unintended effects occur also. The unintended effects are side effects.

Some side effects are common, meaning many people in the study group had them during the clinical trial; therefore, it would not be unusual for someone taking the drug to experience them. When you read about the side effects of a new drug, the common side effects are the ones to note since they are the ones you are most likely to experience.

On the drug sheet that comes with medication from the manufacturer, you will see a list of medication side effects that is very long. Often included in that list is a number indicating the occurrence percentage. Pay attention to that number. Frequently, it’s a low percentage. In clinical trials, companies must report any unexpected reactions during the trial no matter what it is, even if they don’t believe the reaction came from the drug. Therefore, there are many side effects listed that rarely occur.

Since so many side effects are often listed, many companies highlight or bold the side effects that are the most likely to occur. For example, baclofen has the common side effects of drowsiness, dizziness, weakness, tiredness, headache, nausea, constipation, difficulty sleeping, insomnia, and frequent urination. Note that headache, nausea, constipation, and insomnia are bold, indicating more frequent side effects.

Furthermore, most companies warn you of serious side effects that mean you are not responding well to the medication and should contact your doctor. If you experience these, heed that warning and seek medical attention because you could be experiencing an allergic reaction or chemical intolerance to the medicine. For example, with baclofen, call if you experience hives, difficulty breathing, or swelling of your face, lips, tongue, or throat (indicates a severe allergic reaction.) In addition, if you experience severe drowsiness, weak or shallow breathing, confusion, hallucinations, itching, tingling, twitching, fever, or seizure, all are indications of serious side effects that need immediate attention.

The other impact regarding side effects is the cumulative effect of multiple drugs with the same side effect. For example, if you have multiple drugs causing dehydration, nausea, or heart irregularities, you are more likely to experience that side effect. Therefore, if you are experiencing an unpleasant side effect and trying to find a way to eliminate it, see if there is a drug from another family group that doesn’t have that same side effect that might be an alternative.

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