Tizanidine Pharmacology

Tizanidine is primarily broken down by CYP1A2. Ciprofloxacin can inhibit CYP1A2 and cause higher tizanidine concentrations.

Tizanidine has a similar classification as clonidine. Pay attention to adverse effects like hypotension and bradycardia.

When patients taking routine tizanidine stop taking it, there is potential for a discontinuation syndrome that may lead to rebound hypertension.

Dry mouth and CNS depression are common adverse effects of tizanidine.

I discuss important drug interactions on the podcast, be sure to check out my latest project which is a 200+ page book on managing drug interactions in primary care.

Be sure to check out our free Top 200 study guide – a 31 page PDF that is yours for FREE!

Codeine Pharmacology

On this episode, I discuss codeine pharmacology and practical clinical practice pearls.

Codeine is metabolized by CYP2D6 to the active metabolite morphine. I discuss how this can be affected by genetics as well as other medications.

Constipation is a problem with codeine and all opioids in general. Education and making a plan with patients to combat this side effect is important.

Codeine is less potent than other opioids such as fentanyl, hydromorphone, and hydrocodone.

I discuss important drug interactions on the podcast, be sure to check out my latest project which is a 200+ page book on managing drug interactions in primary care.

Be sure to check out our free Top 200 study guide – a 31 page PDF that is yours for FREE!

Nortriptyline Pharmacology

Nortriptyline is a TCA that can be used for depression and various pain syndromes. I discuss other less common diagnoses in this podcast episode as well.

There are a lot of drug interactions with nortriptyline. It is metabolized by CYP2D6, can have additive anticholinergic effects and has been associated with QTc prolongation.

Nortriptyline is very anticholinergic and can blunt the effects of dementia medications.

Dry mouth, dry eyes, sedation, urinary retention, and constipation are a few of the more common adverse effects of nortriptyline.

I discuss important drug interactions on the podcast, be sure to check out my latest project which is a 200+ page book on managing drug interactions in primary care.

Be sure to check out our free Top 200 study guide – a 31 page PDF that is yours for FREE!

Hydroxychloroquine Pharmacology

Hydroxychloroquine is classified as a DMARD and when used chronically, can be helpful in managing rheumatoid arthritis and Lupus.

There have been reports of QTc prolongation with hydroxychloroquine. While not incredibly common, it is important to remember this consideration in patients at risk for QTc prolongation.

Hydroxychloroquine is associated with causing retinopathy. Routine eye exams for monitoring purposes are critical.

Rarely, hydroxychloroquine can be associated with blood disorders like neutropenia and thrombocytopenia. In addition, alterations in liver function have been reported.

I discuss important drug interactions on the podcast, be sure to check out my latest project which is a 200+ page book on managing drug interactions in primary care.

Be sure to check out our free Top 200 study guide – a 31 page PDF that is yours for FREE!

Celecoxib Pharmacology

Celecoxib is easy to remember as its mechanism of action is “COX”-2 Inhibition. This can result in result in reduced prostaglandin formation and help with pain and inflammation.

Kidney function is important to monitor in our patient on celecoxib. It is especially important in patients taking ACE inhibitors, ARBs, and/or diuretics.

While GI bleed may be less likely with celecoxib compared to traditional NSAIDs like indomethacin and ibuprofen, it still needs to be monitored for.

Digoxin concentrations may be increased with the use of celecoxib.

Celecoxib is generally dosed twice per day as the half-life of the drug is in the ballpark of 10-12 hours.

Be sure to check out our free Top 200 study guide – a 31 page PDF that is yours for FREE!

Carbamazepine Pharmacology

Carbamazapine Pharmacology

On this episode, I discuss carbamazepine pharmacology. This drug is most commonly used for seizures, bipolar disorder, or trigeminal neuralgia.

Carbamazepine is an autoinducer and can reduce the concentrations of numerous drugs. Some examples include apixaban, warfarin, rivaroxaban, diltiazem, verapamil, and many more!

Carbamazepine has the potential to cause Steven Johnson’s Syndrome. This has a much greater chance of happening in patients with certain genetics.

Carbamazepine can contribute to SIADH and cause significant hyponatremia.

Carbamazepine has boxed warning for numerous potential events like aplastic anemia, agranulocytosis, and the above-mentioned SJS.

Be sure to check out our free Top 200 study guide – a 31 page PDF that is yours for FREE!