diff --git a/messages.go b/messages.go
index 2320bf7f..f6be9ff9 100644
--- a/messages.go
+++ b/messages.go
@@ -101,6 +101,7 @@ func newWriteBuf(c *Conn, t byte) *WriteBuf {
 // by the Encoder interface when implementing custom encoders.
 type WriteBuf struct {
 	buf     []byte
+	convBuf [8]byte
 	sizeIdx int
 	conn    *Conn
 }
@@ -125,41 +126,32 @@ func (wb *WriteBuf) WriteCString(s string) {
 }
 
 func (wb *WriteBuf) WriteInt16(n int16) {
-	b := make([]byte, 2)
-	binary.BigEndian.PutUint16(b, uint16(n))
-	wb.buf = append(wb.buf, b...)
+	wb.WriteUint16(uint16(n))
 }
 
 func (wb *WriteBuf) WriteUint16(n uint16) (int, error) {
-	b := make([]byte, 2)
-	binary.BigEndian.PutUint16(b, n)
-	wb.buf = append(wb.buf, b...)
+	binary.BigEndian.PutUint16(wb.convBuf[:2], n)
+	wb.buf = append(wb.buf, wb.convBuf[:2]...)
 	return 2, nil
 }
 
 func (wb *WriteBuf) WriteInt32(n int32) {
-	b := make([]byte, 4)
-	binary.BigEndian.PutUint32(b, uint32(n))
-	wb.buf = append(wb.buf, b...)
+	wb.WriteUint32(uint32(n))
 }
 
 func (wb *WriteBuf) WriteUint32(n uint32) (int, error) {
-	b := make([]byte, 4)
-	binary.BigEndian.PutUint32(b, n)
-	wb.buf = append(wb.buf, b...)
+	binary.BigEndian.PutUint32(wb.convBuf[:4], n)
+	wb.buf = append(wb.buf, wb.convBuf[:4]...)
 	return 4, nil
 }
 
 func (wb *WriteBuf) WriteInt64(n int64) {
-	b := make([]byte, 8)
-	binary.BigEndian.PutUint64(b, uint64(n))
-	wb.buf = append(wb.buf, b...)
+	wb.WriteUint64(uint64(n))
 }
 
 func (wb *WriteBuf) WriteUint64(n uint64) (int, error) {
-	b := make([]byte, 8)
-	binary.BigEndian.PutUint64(b, n)
-	wb.buf = append(wb.buf, b...)
+	binary.BigEndian.PutUint64(wb.convBuf[:8], n)
+	wb.buf = append(wb.buf, wb.convBuf[:8]...)
 	return 8, nil
 }
 
diff --git a/pgtype/int4.go b/pgtype/int4.go
index ab993476..29b5dd1b 100644
--- a/pgtype/int4.go
+++ b/pgtype/int4.go
@@ -1,7 +1,6 @@
 package pgtype
 
 import (
-	"encoding/binary"
 	"fmt"
 	"io"
 	"strconv"
@@ -9,8 +8,23 @@ import (
 
 type Int4 int32
 
-func (i *Int4) ParseText(src string) error {
-	n, err := strconv.ParseInt(src, 10, 32)
+func (i *Int4) DecodeText(r io.Reader) error {
+	size, err := ReadInt32(r)
+	if err != nil {
+		return err
+	}
+
+	if size == -1 {
+		return fmt.Errorf("invalid length for int4: %v", size)
+	}
+
+	buf := make([]byte, int(size))
+	_, err = r.Read(buf)
+	if err != nil {
+		return err
+	}
+
+	n, err := strconv.ParseInt(string(buf), 10, 32)
 	if err != nil {
 		return err
 	}
@@ -19,12 +33,22 @@ func (i *Int4) ParseText(src string) error {
 	return nil
 }
 
-func (i *Int4) ParseBinary(src []byte) error {
-	if len(src) != 4 {
-		return fmt.Errorf("invalid length for int4: %v", len(src))
+func (i *Int4) DecodeBinary(r io.Reader) error {
+	size, err := ReadInt32(r)
+	if err != nil {
+		return err
 	}
 
-	*i = Int4(binary.BigEndian.Uint32(src))
+	if size != 4 {
+		return fmt.Errorf("invalid length for int4: %v", size)
+	}
+
+	n, err := ReadInt32(r)
+	if err != nil {
+		return err
+	}
+
+	*i = Int4(n)
 	return nil
 }
 
diff --git a/pgtype/typed_reader.go b/pgtype/typed_reader.go
new file mode 100644
index 00000000..29997338
--- /dev/null
+++ b/pgtype/typed_reader.go
@@ -0,0 +1,104 @@
+package pgtype
+
+import (
+	"encoding/binary"
+	"io"
+)
+
+type uint16Reader interface {
+	ReadUint16() (n uint16, err error)
+}
+
+type uint32Reader interface {
+	ReadUint32() (n uint32, err error)
+}
+
+type uint64Reader interface {
+	ReadUint64() (n uint64, err error)
+}
+
+// ReadByte reads a byte from r.
+func ReadByte(r io.Reader) (byte, error) {
+	if r, ok := r.(io.ByteReader); ok {
+		return r.ReadByte()
+	}
+
+	buf := make([]byte, 1)
+	_, err := r.Read(buf)
+	return buf[0], err
+}
+
+// ReadUint16 reads an uint16 from r in PostgreSQL wire format (network byte order). This
+// may be more efficient than directly using Read if r provides a ReadUint16
+// method.
+func ReadUint16(r io.Reader) (uint16, error) {
+	if r, ok := r.(uint16Reader); ok {
+		return r.ReadUint16()
+	}
+
+	buf := make([]byte, 2)
+	_, err := io.ReadFull(r, buf)
+	if err != nil {
+		return 0, err
+	}
+
+	return binary.BigEndian.Uint16(buf), nil
+}
+
+// ReadInt16 reads an int16 r in PostgreSQL wire format (network byte order). This
+// may be more efficient than directly using Read if r provides a ReadUint16
+// method.
+func ReadInt16(r io.Reader) (int16, error) {
+	n, err := ReadUint16(r)
+	return int16(n), err
+}
+
+// ReadUint32 reads an uint32 r in PostgreSQL wire format (network byte order). This
+// may be more efficient than directly using Read if r provides a ReadUint32
+// method.
+func ReadUint32(r io.Reader) (uint32, error) {
+	if r, ok := r.(uint32Reader); ok {
+		return r.ReadUint32()
+	}
+
+	buf := make([]byte, 4)
+	_, err := io.ReadFull(r, buf)
+	if err != nil {
+		return 0, err
+	}
+
+	return binary.BigEndian.Uint32(buf), nil
+}
+
+// ReadInt32 reads an int32 r in PostgreSQL wire format (network byte order). This
+// may be more efficient than directly using Read if r provides a ReadUint32
+// method.
+func ReadInt32(r io.Reader) (int32, error) {
+	n, err := ReadUint32(r)
+	return int32(n), err
+}
+
+// ReadUint64 reads an uint64 r in PostgreSQL wire format (network byte order). This
+// may be more efficient than directly using Read if r provides a ReadUint64
+// method.
+func ReadUint64(r io.Reader) (uint64, error) {
+	if r, ok := r.(uint64Reader); ok {
+		return r.ReadUint64()
+	}
+
+	buf := make([]byte, 8)
+	_, err := io.ReadFull(r, buf)
+	if err != nil {
+		return 0, err
+	}
+
+	return binary.BigEndian.Uint64(buf), nil
+}
+
+// ReadInt64 reads an int64 r in PostgreSQL wire format (network byte order). This
+// may be more efficient than directly using Read if r provides a ReadUint64
+// method.
+func ReadInt64(r io.Reader) (int64, error) {
+	n, err := ReadUint64(r)
+	return int64(n), err
+}
diff --git a/value_reader.go b/value_reader.go
index 249b8ba3..c91a21af 100644
--- a/value_reader.go
+++ b/value_reader.go
@@ -4,6 +4,8 @@ import (
 	"errors"
 )
 
+var errRewoundLen = errors.New("len was rewound")
+
 // ValueReader is used by the Scanner interface to decode values.
 type ValueReader struct {
 	mr                  *msgReader
@@ -154,3 +156,28 @@ func (r *ValueReader) ReadBytes(count int32) []byte {
 
 	return r.mr.readBytes(count)
 }
+
+type valueReader2 struct {
+	*ValueReader
+}
+
+func (r *valueReader2) Read(dst []byte) (int, error) {
+	if r.err != nil {
+		return 0, r.err
+	}
+
+	src := r.ReadBytes(int32(len(dst)))
+
+	copy(dst, src)
+
+	return len(dst), nil
+}
+
+func (r *valueReader2) ReadUint32() (uint32, error) {
+	if r.err == errRewoundLen {
+		r.err = nil
+		return uint32(r.Len()), nil
+	}
+
+	return r.ValueReader.ReadUint32(), nil
+}
diff --git a/values.go b/values.go
index ee53edfc..85c7ad3d 100644
--- a/values.go
+++ b/values.go
@@ -1789,13 +1789,15 @@ func decodeInt4(vr *ValueReader) int32 {
 		return 0
 	}
 
+	vr.err = errRewoundLen
+
 	var n pgtype.Int4
 	var err error
 	switch vr.Type().FormatCode {
 	case TextFormatCode:
-		err = n.ParseText(vr.ReadString(vr.Len()))
+		err = n.DecodeText(&valueReader2{vr})
 	case BinaryFormatCode:
-		err = n.ParseBinary(vr.ReadBytes(vr.Len()))
+		err = n.DecodeBinary(&valueReader2{vr})
 	default:
 		vr.Fatal(ProtocolError(fmt.Sprintf("Unknown field description format code: %v", vr.Type().FormatCode)))
 		return 0