Ropivacaine is a member of the amino amide class of local anesthetics and is supplied as the pure S-(-)-enantiomer. It produces effects similar to other local anesthetics via reversible inhibition of sodium ion influx in nerve fibers. Ropivacaine is less lipophilic than bupivacaine and is less likely to penetrate large myelinated motor fibers, resulting in a relatively reduced motor blockade. Thus, ropivacaine has a greater degree of motor-sensory differentiation, which could be useful when the motor blockade is undesirable. The reduced lipophilicity is also associated with decreased potential for central nervous system toxicity and cardiotoxicity. Ropivacaine is indicated for the production of local or regional anesthesia for surgery and for acute pain management.

Bupivacaine is a widely used local anesthetic agent. Bupivacaine is often administered by spinal injection prior to total hip arthroplasty. It is also commonly injected into surgical wound sites to reduce pain for up to 20 hours after surgery. In comparison to other local anesthetics it has a long duration of action. It is also the most toxic to the heart when administered in large doses. Bupivacaine blocks the generation and the conduction of nerve impulses, presumably by increasing the threshold for electrical excitation in the nerve, by slowing the propagation of the nerve impulse, and by reducing the rate of rise of the action potential. Bupivacaine binds to the intracellular portion of sodium channels and blocks sodium influx into nerve cells, which prevents depolarization. In general, the progression of anesthesia is related to the diameter, myelination and conduction velocity of affected nerve fibers. The analgesic effects of bupivicaine are thought to potentially be due to its binding to the prostaglandin E2 receptors, subtype EP1 (PGE2EP1), which inhibits the production of prostaglandins, thereby reducing fever, inflammation, and hyperalgesia. Bupivacaine sometimes used in combination with epinephrine to prevent systemic absorption and extend the duration of action.

Dexivacaine is a local anesthetic drug that has minimal and non-significant side effects.

(R)-Ropivacaine (Dextroropivacaine) is a voltage-dependent potassium channel blocker with local anesthetic activity. (S)-Ropivacaine is a medication used for the production of local or regional anesthesia for surgery and for acute pain management. Ropivacaine shows a difference in channel blockade between two enantiomers, and R-Ropivacaine shows greater cardiotoxicity than (S)-Ropivacaine. (R)-Ropivacaine is the impurity in commercial formulations of Ropivacaine.