Drug List 13 Mod 200 Pharmacology lecture
Centrally acting skeletal muscle relaxants • Brand: Lioresal • Generic: baclofen (back-lo-fen) • Classification: muscle relaxant • Indications: relief of muscle spasticity resulting from MS or spinal cord injury/disease. Baclofen is NOT indicated for use in rheumatic disorders, stroke, cerebral palsy or parkinsons. Off label use in intractable hiccoughs, trigeminal neuralgia (Trigeminal neuralgia is a painful condition of the nerve responsible for most facial sensation.) • Action: decreases frequency and severity of muscle spasms • Warnings: D/D, constipation, no alcohol. • Intrathecal: should only be used if unresponsive to PO or have intolerable CNS side effects. Black box warning about sudden withdrawal causing rebound spasticity, altered mental states, even death
Brand: Soma • Generic: carisoprodol (car-iss-oh-pro-dol) • Classification: muscle relaxant • Indications: relief of discomfort associated with acute, painful musculoskeletal conditions in adults. Indicated for short term use only. • Action: Does not directly relax tense skeletal muscles. In animals, it depresses the CNS by blocking interneuronal activity in the spinal cord, producing sedation. Metabolizes into meprobamate (CIV) • Warnings: D/D, n&v, no alcohol. • Drug interactions: alcohol, TCAs, phenothiazines
Brand: Flexeril • Generic: cyclobenzaprine (cy-cloh-benz-ah-preen) • Classification: muscle relaxant • Indications: relief of muscle spasm associated with acute, painful musculoskeletal conditions. Not effective for muscle spasm due to CNS disease. Off label: fibromyalgia • Action: relieves muscle spasm of local origin without interfering with muscle function. • Warnings:cyclobenzaprine is structurally similar to TCAs. Do not use w/in 14 days of MAOIs. Avoid abrupt cessation, taper over 1-2 weeks. Avoid alcohol, D/D.
Brand: Robaxin • Generic:methocarbamol (meth-oh-car-bah-mol) • Classification: muscle relaxant • Indications: relief of muscle spasm associated with acute, painful musculoskeletal conditions. • Action: works in the spinal cord causing skeletal muscle relaxation • Warnings: avoid abrupt cessation, taper over 1-2 weeks. Urine discoloration of green, black or brown is possible. Avoid alcohol, D/D. • IV use: recumbent position may reduce the incidence of side reactions. Rate of injection should not exceed 3ml/minute. Methocarbamol is a hypertonic solution and vascular extravasation must be avoided
Brand name: Skelaxin • Generic name: Metaxalone • Classifications: muscle relaxant • Indication: relief of muscle spasm associated with acute, painful musculoskeletal conditions. • Action: general CNS depression. • Warnings: avoid alcohol, D/D.
Brand name: Zanaflex • Generic name: Tizanidine • Class: muscle relaxant • Indication: management of muscle spasticity • Action: alpha-2 adrenergic receptor agonist. Reduces facilitation of spinal motor neurons. • Warnings: D/D, avoid alcohol. May cause hypotension. • Drug interactions: CYP1A2 inhibitors, cipro, fluvoxamine
Anticonvolsants • FDA medwatch bulletin on antiepileptic from 2008-refers to suicidality risk with antiepileptic medications. • Brand:Depakote • Generic:divalproex (div-al-pro-ex) • Classification: anticonvulsant • Indications: seizure control, manic episodes in bipolar disorder, migraine prophylaxis. • Action: carboxylic acid antiepileptic. Exact mechanism of action is unknown, it is thought to affect brain concentrations of GABA
Depakote cont. • Warnings: black box warning about possible liver failure, teratogenic effects ( neural tube defects), pancreatitis. Avoid alcohol, antacids, dairy products. May cause false positive urine test for ketones. Do not take medication with carbonated beverages. • Drug interactions: alcohol, antacids, carbamazepine, clonazepam, diazepam, erythromycin, lamotrigine, olanzapine, phenytoin,TCAs, warfarin, AZT • Do not discontinue abruptly
Brand: Neurontin • Generic: gabapentin (gah-bah-pen-tin) • Classification: anticonvulsant • Indications: Epilepsy, postherpeticneuralgia. • Off-label: treatment of tremors associated with MS, bipolar disorder. Postmenopausal or cancer related hot flashes, neuralgia • Action: mechanism of action is unknown. • Warnings: D/D, do not take with antacids, avoid alcohol • Drug interactions: antacids, morphine, BCPs, alcohol • Taper slowly
Brand: Luminal (CIV) • Generic: phenobarbitol (feen-oh-bar-bih-tol) • Classification: anticonvulsant • Indications: anticonvulsant for the treatment of generalized and partial seizures. Emergency control of acute seizure disorders due to status epilepticus, meningitis, tetanus, eclampsia, toxicity of local anesthetics. May be used investigationally for hyperbilirubinema and chronic cholestasis • Action: decreases impulse transmission and increases seizure threshold at cerebral cortex • Warnings: avoid alcohol and CNS depressants. May cause pardoxic excitement in the elderly. May accentuate emotional disturbances and phobias. Irritability, hyperactivity may occur in children. • Drug interactions: alcohol, MAOIs, BCPs, anticonvulsants
Brand:Dilantin • Generic:phenytoin (fehn-ee-toyn) • Classification: anticonvulsant • Indications: generalized tonic-clonic (grand mal), simple partial and complex partial seizures. Prevention of seizures following head trauma/neurosurgery. Ventricular arrhythmias. • Action: inhibits spread of seizure activity in the motor cortex. • Warnings: avoid alcohol. Practice good dental hygiene to minimize development of gingival hyperplasia. • Drug interactions: numerous! • Various dosage forms are not interchangeable